photonicroadsme_rd report on metamaterials
DESCRIPTION
PhotonicRoadSME_RD Report on MetamaterialsTRANSCRIPT
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PhotonicRoadSME is funded by the European
Commission under the 7th Framework Programme
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Table of content
Table of content ........................................................................................................ 3
1. Introduction ........................................................................................................... 6
1.1. Definition of the material category ................................................................................................ 6
1.2. Overview ....................................................................................................................................... 6
1.2.1 Magnetic response: split-ring resonators (SRR) .................................................................... 7
1.2.2 Electric response: straight-wire medium ................................................................................ 7
1.2.3 Electric response: straight-wire medium ................................................................................ 8
2. Summary of European and national R&D funded projects ............................... 8
2.1. Metamaterials: from radio-frequencies to optical frequencies ................................................... 11
2.2. Nanolight.es: Light Control on the Nanoscale ............................................................................ 11
2.3. PhOREMOST (Network of excellence) ...................................................................................... 12
2.4. Metamorphose: Metamaterials organized for radio, millimeter wave and photonic supperlattice
engineering (Network of excellence) ................................................................................................. 13
2.5. MEMS tuneable metamaterials for smart wireless applications (TUMESA) .............................. 15
2.6. Photonic metamaterials (PHOME) ............................................................................................. 16
2.7. Optimal design and fabrication of electromagnetic metamaterials for millimeter and microwave
applications ........................................................................................................................................ 17
2.8. Advanced computational studies of dynamic phenomena in magnetic nano-materials ............ 18
2.9. Building radio-frequency identification solutions for the global environment (BRIDGE) ............ 19
2.10. Development and analysis of left-handed materials (DALHM) ................................................ 19
2.11. Electromagnetic and spin wave interactions in nanostructure-based metamaterials and
devices (EMSWIM) ............................................................................................................................ 20
2.12. Plasmonic cavity quantum electrodynamics with diamond-based quantum systems
(PLACQED) ....................................................................................................................................... 21
2.13. Self-organized nanomaterials for tailored optical and electrical properties (NANOGOLD) ..... 21
2.14. Nanochemistry and self-assembly routes to metamaterials for visible light (METACHEM) .... 22
2.15. Optically controlled growth of nanotubes and nanowires (J2923 Optisch gesteuertes
Wachstum von Nanoröhren und Nanodrähten)................................................................................. 23
2.16. Resonance-domain metamaterials for sub-wavelength optics................................................. 23
2.17. Metamaterials for photonics, high frequencies and optical networks (Metamatériaux pour la
photonique, les hyperfréquences et l'optique des réseaux) .............................................................. 24
2.18. Nonlinear Photonics with Metallic Nanostructures on Top of Dielectrics and Waveguides ..... 24
2.19. Analysis and Synthesis of resonant Antenna Structures based on Metamaterials (Analyse und
Synthese von resonanten Antennenstrukturen basierend auf Metamaterialien) .............................. 25
2.20. ZIK – Ultraoptics Project: Design and Implementation of functional Metamaerials by
Nanostructuring and Application of those structures in Complex Photonic Systems (ZIK Ultraoptics -
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Projekt: Design und Realisierung hochfunktioneller optischer Metamaterialien durch
Nanostrukturierung sowie deren Anwendung in komplexen photonischen Systemen) .................... 26
2.21. METAMAT - 3D Photonic Metamaterials (METAMAT - Photonische Metamaterialien - 3D-
Metamaterialien) ................................................................................................................................ 26
2.22. Applicable verification of hybrid eutectic systems for metamaterials production ..................... 26
2.23. Production eutectic systems by “micro-pulling down” .............................................................. 26
2.24. Large area fabrication of 3D negative index metamaterials by Nanoimprint Lithography
(NIM_NIL) .......................................................................................................................................... 27
2.25. NANOSTRUCTURED PHOTONIC METAMATERIALS ........................................................... 28
2.26. Active Plasmonics and Lossless Metamaterials ...................................................................... 29
2.27. Advanced Design and Control of Active and Passive Metamaterials : from Microwaves ........ 29
2.28. Negative index metamaterials for visible-light optics ............................................................... 30
2.29. Building Ceramic Metamaterials from Nanoparticles: A combined Modelling, Tomography and
In-situ Loading Study ......................................................................................................................... 31
2.30. NANOSTRUCTURED METAFILMS: A NEW PARADIGM FOR PHOTONICS ....................... 33
3. Literature survey .................................................................................................34
3.1. Overview of publications............................................................................................................. 34
3.2. Metamaterial antennas ............................................................................................................... 36
3.3. Cloaking ...................................................................................................................................... 37
3.4. Superlenses ................................................................................................................................ 39
3.5. 3.5 References ........................................................................................................................... 41
4. Current applications ............................................................................................42
4.1. Information and Communication Technologies .......................................................................... 42
4.1.1 Optical interconnect devices and structures based on metamaterials - US 2008212921 (A1)
....................................................................................................................................................... 42
4.1.2 Negative-refraction metamaterials using continuous metallic grids over ground for
controlling and guiding electromagnetic radiation - US 2008204164 (A1) .................................... 43
4.1.3 Use of left-handed metamaterials as a display, particularly on a hob, as well as display and
display method - US 2007267406 (A1) ......................................................................................... 43
4.1.4 Nonlinear optical devices based on metamaterials - WO 2007133727 (A1) ....................... 43
4.1.5 Antennas, devices and systems based on metamaterial structures - US 2008258981 (A1) 44
4.1.6 Metamaterial antenna arrays with radiation pattern shaping and beam switching - US
2008258993 (A1) ........................................................................................................................... 44
4.1.7 Single-Feed Multi-Cell Metamaterial Antenna Devices US2009251385 (A1) .................... 44
4.1.8 Tunable delay system and corresponding method - WO 2008116289 (A1) ........................ 44
4.1.9 Compact dual-band resonator using anisotropic metamaterial - US 2008204327 (A1) ...... 45
4.1.10 Metamaterial structures for light processing and methods of processing light - WO
2008094543 (A1) ........................................................................................................................... 45
4.1.11 Method and apparatus for reduced coupling and interference between antennas ............ 45
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4.2. Environment ............................................................................................................................... 46
4.2.1 Molecular and photonic nanostructures, optical biomaterials, photosensitizers, molecular
contrast agents, and metamaterials - WO 2008130383 (A2) ........................................................ 46
4.3. Health & Well-Being ................................................................................................................... 46
4.3.1 Photonic funnels and anisotropic waveguides for subdiffraction light compression and pulse
management at the nanoscale - US 2008219628 (A1) ................................................................. 46
4.4. Safety & Security ........................................................................................................................ 46
4.4.1 Efficient terahertz sources by optical rectification in photonic crystals and metamaterials
exploiting tailored transverse dispersion relations - US 2007297734 (A1) ................................... 46
4.4.2 Active terahertz metamaterial devices - WO 2008121159 (A2) ........................................... 47
4.4.3 Three-dimensional left-handed metamaterial - WO 2008120556 (A1) ................................ 47
4.4.4 Security mark - WO 2008110775 (A1) ................................................................................. 47
4.4.5 System, method and apparatus for cloaking - US 2008165442 (A1) ................................... 48
4.4.6 Electromagnetic cloaking method - CA 2590307 (A1) ........................................................ 48
4.4.7 Active radar system .............................................................................................................. 48
4.5. Others ......................................................................................................................................... 48
4.5.1 Metamaterials and resonance materials based on composites of liquid crystal colloids and
nano particles - SI 22508 (A) ......................................................................................................... 48
4.5.2 Metamaterials and resonant materials based on liquid crystal dispersions ......................... 49
of colloidal particles and nanoparticles - EP 1975656 (A1) ........................................................... 49
4.5.3 Enhanced substrate using metamaterials - WO 2007069224 (A2) ...................................... 49
4.5.4 Fabrication of semiconductor metamaterials - US 2008138571 (A1) .................................. 49
4.5.5 Variable metamaterial apparatus - WO 2007098061 (A2) ................................................... 50
5. Barriers .................................................................................................................50
6. Trends and future applications ..........................................................................51
6.1. Waveguide miniaturization ......................................................................................................... 51
6.2. Dispersive waveguides ............................................................................................................... 52
6.3. Antennas / antenna arrays ......................................................................................................... 53
6.4. High impedance surfaces and artificial magnetic conductors .................................................... 53
6.5. Tuneable materials ..................................................................................................................... 54
6.6. Summary .................................................................................................................................... 54
7. Information sheets on relevant photonic materials ..........................................57
8. Imprint ..................................................................................................................58
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1. Introduction
1.1. Definition of the material category
As its name may suggest, metamaterials are materials whose properties are different from materials
available in nature. In general, these materials get their beyond-nature properties from their structure
rather than their composition.
Following the ideas from Padilla et al., engineered, periodic materials composed of designed metallic
and/or dielectric inclusions with dimensions smaller than the working wavelength can display striking
and unique electromagnetic properties, not inherent to their individual constituent “basic blocks”.
These artificially nanostructures, known as metamaterials, have “the potential to fill critical voids in the
electromagnetic spectrum where the material response of common optoelectronic elements is limited
and enable the construction of novel devices”. As a matter of fact, they can be characterized by
spatially averaged dielectric properties at the range of interest, µ and ε. In the last years,
metamaterials showing features like negative refractive index behaviour and enhancement control on
the magnetic field at optical frequencies have drawn significant attention. Thus, the potential of
metamaterials to facilitate new developments in electromagnetism paves the way to the design,
fabrication and characterization on the nanoscale of superlenses, filters, and , eventually, cloaking
devices, among some of the most remarkable applications in this field.
Although there is an increasingly interest in different structures that could act as metamaterials at
optical frequencies, most of the designs at nanoscale mimic those at lower frequencies, based on
many well-know devices that have been characterized in the lab. Consequently, the main efforts rely
on nanoscaled periodic structures made of metallic (or dielectric) inclusions on a dielectric or (metallic)
matrix. There exist also alternative approaches to get metamaterials working at higher frequencies
through plasmonic effects (i.e. beaming). At optical frequencies the first objective is to prove the
feasibility of lensing devices with the help of artificial materials like plasmonic devices, split-ring
resonators and engineered thin sheets. At terahertz frequencies, the main goal is to achieve left-
handed materials easily. In both ranges of frequencies, the cost of fabrication and testing is high.
Nonetheless, visible frequency applications seem to be less probable in the short run than at longer
wavelengths We must prevent to not to consider photonic crystals as a kind of metamaterial, in the
sense we are discussing, because of the dispersion effects unavoidable in these structures. In sharply
contrast, metamaterials present a well-defined index of refraction at the range of interest, which is
independent from the wave-vector of the illuminating radiation.
1.2. Overview
Taking into account the dimension of the structures involved in the design, fabrication and
characterization of metamaterials that could have the highest potential, they can be classified as
follows.
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1.2.1 Magnetic response: split-ring resonators (SRR)
Split-ring resonators (SRR) are one of the most common elements used to fabricate metamaterials.
They are non-magnetic materials, which are usually fabricated from circuit board material to create
metamaterials. SRRs are pairs of concentric annular rings with splits in them at opposite ends. The
rings are made of metal like copper and have small gap between them. They can be arranged in an
array to form an effective magnetic material. Its performance and behaviour as a metamaterial can be
understood in terms of an LC resonator, displaying a different response (in phase or out of phase with
the interacting electromagnetic field) depending on the frequency of the field.
A magnetic flux penetrating the metal rings will induce rotating currents in the rings, which produce
their own flux to enhance or oppose the incident field (depending on the SRR's resonant properties).
This field pattern is dipolar. Due to splits in the rings the structure can support resonant wavelengths
much larger than the diameter of the rings. This would not happen in closed rings. The small gaps
between the rings produces large capacitance values which lower the resonating frequency, as the
time constant is large. The dimensions of the structure are small compared to the resonant
wavelength. This results in low radiative losses, and very high quality factors.
At frequencies below the resonant frequency, the real part of the magnetic permeability of the SRR
becomes large, and at frequencies higher than resonance it will become negative. This negative
permeability can be used with the negative dielectric constant of another structure to produce negative
refractive index materials. Increasing the number of splits increases the magnetic resonance
frequency drastically, since the amount of decrease in the capacitance of the system is very large.
1.2.2 Electric response: straight-wire medium
It is mandatory to dispose of a medium with negative response to the electric field, in order to design a
left-handed material. Naturally occurring materials that give rise to negative response to the electric
field component of the electromagnetic wave at optical frequencies are well-know. For instance, any
metal illuminated by a electromagnetic wave with a frequency below its plasma frequency has
negative values for its permittivity, which stems from the response of the free electrons of the metal.
Nevertheless, a wire (1D) lattice made of metallic fibers in a bulk dielectric offers far more flexibility to
control the electric response to the field than a usual metal at optical frequencies. This is due to the
dependence of the resonance frequency of the equivalent permittivity with the dimension and
geometry of the nanostructure. In the context of negative-index metamaterials, the wire lattice and its
variants are an excellent approach for designing and fabricating a medium for which ε < 0.
Because the plasma frequency can be tuned by geometry, the region of moderately negative values
can be forced to happen in the whole rane of the spectrum, from Ghz to optical frequencies. There are
also proposals to reproduce 2D periodic arrays of units made of noble metal/semiconductor on a
dielectric substrate to achieve a negative electric response in the same fashion as SRR acts on the
magnetic field component.
Combining both kinds of structures in different ways, a left-handed material can be created. The work
frequency can be tuned, as it depends on the dimension of the unit cells of the materials
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aforementioned. It must be mentioned that the smaller the dimensions of the unit cells of the
structures analyzed above, the poorer the performance of the nanostructure based on the combination
of SRR and wires. Several methods were proposed to overcome this problem. The simplest one is to
add more capacitive gaps to the original SRR design.
1.2.3 Electric response: straight-wire medium
To beat the limitations at higher frequencies of the previous structures, some alternatives have been
put forward to obtain materials working with an n < 0 at visible and near-infrared wavelengths. Some
of them are periodic arrays of parallel metallic nano-rods on a dielectric substrate, periodic arrays of
voids on metallic sheets and “fishnet” nanostructures on metallic sheets. All of them can be
considered 2D nanostructures. Some others take advantage of the plasmonic effects that appear in
the interaction of light with them.
2. Summary of European and national R&D funded projects
In this section, a list of some representative European and National initiatives (Germany, France,
Spain, Finland, Austria, Switzerland, Poland, UK) in the field of metamaterials during the last years is
presented. A project search was conducted using following keywords:
keyword
hits in
German
y
hits in
France
*)
hits in
Spain
hits in
Finland
*)
hits in
Austria
hits in
Switzerl
and
hits in
Poland
hits in
UK *)
hits in
Cordis
metamaterials 9 1 2 1 0 1 2 6 12
split-ring
resonator 0 0 0 0 0 0
negative
refractive index 0 0 0 0 0 2
superlens 0 0 0 0 0 0
cloaking 1 0 0 0 0 1
*) there was no database available, project search was undertaken “by hand” (web search)
**) database available but not searchable in a systematic manner
Following databases have been searched:
DFG Germany: http://gepris.dfg.de/gepris/
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BMBF Germany:
http://foerderportal.bund.de/foekat/jsp/SucheAction.do?actionMode=searchmask
Madri+D database Spain: http://www.madrimasd.org/Investigadores/buscador-proyectos-
investigacion/default.asp
FWF Austria: http://www.fwf.ac.at/de/projects/projekt_datenbank.asp
ARAMIS Switzerland: http://www.aramis.admin.ch/Default.aspx
Ministry of Science and Education Poland (2007 - ): http://nauka-
polska.pl/dhtml/raportyWyszukiwanie/wyszukiwaniePraceBadawcze.fs?lang=pl
Ministry of Science and Education Poland (2006 - 2007):
http://www.nauka.opi.org.pl/granty/zaawansowane.htm
Pôle Optique & Photonic France: http://www.popsud.org/
Ministère de l'Enseignement supérieur et de la Recherche France:
http://www2.enseignementsup-recherche.gouv.fr/appel/index.htm
FinNano 2005-2010 Finland:
http://akseli.tekes.fi/opencms/opencms/OhjelmaPortaali/ohjelmat/NANO/en/etusivu.html
Engineering and Physical Sciences Research Council EPSRC database UK:
http://gow.epsrc.ac.uk/ListProgrammes.aspx
Cordis Project database for FP7: http://cordis.europa.eu/fp7/projects_en.html
Cordis Project database for FP6: http://cordis.europa.eu/fp6/projects.htm
A total of 30 national and international R&D funded projects have been identified, examined and
summarized. The table shown below gives an idea of the domain of applications of the projects
mentioned (indicated in grey color) as well as the origin of funding.
Project
# ICT Environment
Health & Well-
Being
Safety &
Security Funding origin
1 optical filters,
superlenses super-lenses Spain
2 optical circuits,
data storage sensors sensors Spain
3 EC
4 optical circuits,
optical antennas
apertures,
imaging systems EC
5
secure high-
capacity
communication
systems
atmospheric
remote sensing,
spectroscopy,
radio astronomy
radar EC
6
thin-film optical
isolators, electro-
optic modulators,
"perfect lenses" EC
10
optical switching,
"perfect lenses"
7 miniaturised
antennas EC
8 EC
9 RIFD tags EC
10
RF absorbers, RF
lenses, optical
filters
EC
11
waveguides,
microcavities,
optical filters
EC
12 EC
13 EC
14 EC
15 Austria
16 light sources Finland
17 optical networks France
18 Germany
19 antennas Germany
20 Germany
21 Germany
22 Poland
23 Poland
24 EC
25 telecoms, data
storage
energy, light
generation,
sensors
sensors, imaging
sensors, imaging,
security
applications
UK
26 slow light
applications
slow light
applications UK
27 slow light,
waveguides
slow light
applications UK
28 superlens superlens UK
29 UK
30
miniaturised
devices, e.g.
optical filters,
splitters,
modulators etc.
UK
Total 17 3 8 2
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2.1. Metamaterials: from radio-frequencies to optical frequencies
Project description
The project aims to investigate different configurations of metamaterials based on SRR resonators
and complementary structures to design filters, superlenses and frequency-selective surfaces from the
millimetric/microwave regime to the optical range. Although the main research lines are devoted to
applications outside the visible range, most of the designs are expected to serve as basis for future
devices at optical frequencies.
Start date: 01/01/2007
End date: 31/12/2009.
Funding organization: Junta de Andalucia (Spain)
Photonic structures studied: SRR structures and their variants
Project cost: 157.999,88
Participant:
Universidad de Sevilla (Spain)
2.2. Nanolight.es: Light Control on the Nanoscale
Project description
NanoLight aims to develop nanoscale light technology for applications in sensing, nanoimaging,
optical circuitry and data storage, the key components of future information technology. The
experimental research comprises nanophotonics, plasmonics, nanofabrication, near field microscopy,
single molecule detection, photonic crystals and nonlinear optics, and thus covers the most important
current approaches to nanoscale light technology. These methods will be exploited to investigate and
control the generation, confinement and flow of light energy on the nanoscale. The theoretical part is
essential to provide concepts and guidelines to design suitable schemes for the creation of highly
localized spatio-temporal fields, to calculate plasmon and shape resonances, local density of states,
nanophotonic forces and the response of embedded quantum systems. NanoLight consolidates a
Spanish network acting as an international reference in this field. The unique financial injection
provided by the Consolider program will be used to invest in the future both in people (at least 25 new
high level research positions) and in national high-tech experimental infrastructure. NanoLight fosters
collaborations with national and international industry, as well as training activities.
Start date: 01/01/2007
End date: 31/12/2007
Funding organization: Spanish Ministry of Technology and Innovation
Photonic structures studied: Nanoplasmonic structures, photonic crystals and similar structures
Project cost: 6.685.000 €
Participants:
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Instituto de Ciencias Fotonicas (Spain)
Instituto de Investigación en Inteligencia Artificial – CSIC (Spain)
Universidad Autonoma de Barcelona (Spain)
Universidad Politécnica de Madrid (Spain)
Universidad Politécnica de Valencia (Spain)
Universidad Rey Juan Carlos (Spain)
Universidad de Llerida (Spain)
2.3. PhOREMOST (Network of excellence)
Project description
PhOREMOST is a 4-year European project established in 2004, in the area of nanophotonics and
molecular photonics, to address the near- and long-term needs of photonic functional components.
The network aims to enhance European research in nanophotonics by integrating students and
researchers working in these fields to realise the underpinning science and engineering for molecular-
based optical components, hence nanophotonics to access the molecular scale. Nanophotonics is
defined as the science and engineering of light-matter interactions where, on the one hand,
interactions take place within the wavelength and subwavelength scales and, on the other hand, the
physical, chemical and structural nature of artificially or natural nanostructured matter determines
these interactions.
The network programme is divided into 4 main activities:
Integration
Research
Spreading of Excellence
Management
Start date: October 2004
End date: September 2008
Funding organization: European Comission
Photonic structures studied: Nanophotonic structures
Project cost: 4.500.000 €
Participants:
Tyndall National Institute (Ireland)
European Laboratory for Non-Linear Spectroscopy (Italy)
Institut de Ciències Fotóniques (Spain)
University of Exeter (United Kingdom)
Consejo Superior de Investigaciones Cientificas (Spain)
University of Southampton (United Kingdom)
Centro Ricerche Fiat Societa Consortile per Azioni (Italy)
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Bilkent Universites (Turkey)
Université de Marseille III (France)
Koc University (Turkey
Universita Delgi Studi Roma « la Sapienza » (Italy)
Centre National de la Recherche Scientifique (France)
Vilnius Pedagogical University (Lithuania)
Technical Research Cnetre of Finland (Finland)
Institute of Solid State Physics (Russia)
Technische Universität Dresden (Germany)
Ioffe Physico-Technical Institute (Russia)
Institute of Molecular and Atomic Physics (Belarus)
Chalmers Tekniska Hoegskola Aktiebolag (Sweden)
Weizmann Institute of Science (Israel)
Université de Montpellier II (France)
Kungliga Teckniska Hogskolan (Sweden)
Universita Politecnica de Catalunya (Spain)
Universita degli Studi di Pavia (Italy)
University of Oxford (United Kingdom)
Institutul National de Cercetare Dezvoltare Pentru Fizica (Romania)
Universitaet Dortmund (Germany)
Ecole Normale Supérieure Cachan (France)
Queen’s University of Belfast (United Kingdom)
Nanocomms Ltd (Ireland)
Foundation for Research and Technology (Greece)
Stichting voor Fundamenteel Onderzoek der Materie (The Netherlands)
Consorzio Ricerche Elaborazione Communtazione Ottica (Italy)
Bergische Universitatet Wuppertal (Germany)
2.4. Metamorphose: Metamaterials organized for radio, millimeter
wave and photonic supperlattice engineering (Network of
excellence)
Project description
Metamaterials are artificial electromagnetic (multi-)functional materials engineered to satisfy the
prescribed requirements. The prefix meta means after, beyond and also of a higher kind. Superior
properties as compared to what can be found in nature are often underlying in the spelling of
metamaterial. These new properties emerge due to specific interactions with electromagnetic fields or
due to external electrical control. Electromagnetic metamaterials will play a key role in providing new
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functionalities and enhancements to the future electronic devices and components, such as high-
speed circuits, multifunctional smart miniature antennas and apertures, high-resolution imaging
systems, smart skins, and so forth. After all, these systems (and others) are built on substrates and
superstrates whose electromagnetic response functions define the design and performance of the
systems. Consider a particular but characteristic example for the applicability of metamaterials:
recently, the theoretical concept of planar perfect lenses with "lefthanded" metamaterials was
proposed. Such a perfect lens would enable to circumvent resolution limitations in many optical or
electromagnetic systems beyond the diffraction limit. Multitudinous applications in many areas of
information technology and life science can be envisaged just for this single particular example, like
e.g. better imaging systems, higher capacity optical data storage systems, more compact integrated
optical telecom solutions, etc. Joint research activities of this collaboration will include composite
materials with extreme electromagnetic properties (such as "left-handed" media and materials with
null-valued effective parameters), electrically controllable materials, stop band materials,
metageometries like fractals and quasi-periodical structures, artificial surfaces and sheets.
Metamaterials are, in essence, the materials of the future, since the main purpose for their study is to
be able to go beyond where naturally occurring substances and current materials research have taken
us. By combining different microscopic elements into large-scale designs, one will be able not only to
create materials with fundamentally new properties but also to fabricate others that have properties on
demand, as required by new technologies. In particular, new electromagnetic properties will allow us
to control microwaves, millimetre waves, and optical light in revolutionary ways. This is the context in
which this project is framed.
Start date: 2004
End date: 2008
Funding organization: European Commission
Photonic structures studied: Metamaterials
Project cost: 4.400.000 € euros
Participants:
Helsinki University of Technology (Finland)
Université Catholique de Louvain (Belgium)
Universidad del País Vasco (Spain)
Swiss Federal Institute of Technology (Switzerland)
University of Southampton (United Kingdom)
Bilkent University (Turkey)
Universidad Publica de Navarra (Spain)
University of Glasgow (United Kingdom)
Siegen University (Germany)
St. Petersburg Electrotechnical University (Russia)
FORTH - Institute of Electronic Structure and Laser (Greece)
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Warsaw University (Poland)
University Roma Tre (Italy)
Loughborough University (United Kingdom)
University of Siena (Italy)
Thales Research & Technology (France)
Universitat Politecnica de Catalunya (Spain)
Queen's University of Belfast (United Kingdom)
Université Paris-Sud (France)
Universidad Autonoma de Barcelona (Spain)
Institute of Electronic Materials Technology (Poland)
2.5. MEMS tuneable metamaterials for smart wireless applications
(TUMESA)
Project description
The proposed project focuses on development of tuneable metamaterials and metasurfaces based on
microelectromechanical systems (MEMS) and their integration to smart wireless systems such as
radar, secure high-capacity communication systems, radio astronomy, atmospheric remote sensing,
spectroscopy, etc. MEMS allow miniaturisation of electronic components, reduce their cost in batch
production and effectively compete with semiconductor and ferroelectric based technologies in terms
of losses at millimetre wavelengths. Metamaterials provide a way to design devices with unique and
engineered electromagnetic properties. The advantage of convergence between MEMS and
metamaterials is ability to create novel miniaturized reconfigurable low-loss and cost-effective wireless
devices with innovative self-adapting mechanisms. In addition to industrial and technological
objectives, a number of socio-economic challenges urge research in smart wireless applications. EU
authorities have launched a program to reduce fatal road accidents by 50% by 2010, with the focus on
driver assistance and on-board safety systems for accident reduction, including automotive radar. For
this purpose, the European Telecommunication Standard Institute (ETSI) has already produced a
standard for automotive radar in the 79 GHz range. The main objectives of the proposed project are to
develop novel on-chip phase shifting and beam-steering devices based on MEMS tuneable high-
impedance surfaces, integrate developed phase shifting components in novel space-efficient antenna
arrays on a single chip, elaborate novel concepts for implementating the beam-steering devices and
antenna arrays in cost-efficient radar sensor and future high-capacity wireless communication systems
and evaluate fabricated prototypes at a system level.
Start date: 01/06/2008
End date: 31/05/2011
Funding organization: European Commission, FP7
Photonic structures studied: tuneable metamaterials
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Project cost: 2.530.000 €
Participants:
Université de Rennes I (France)
Autocruise S.A.S. (France)
Teknillinen Korkeakoulu (Finland)
Microcomp Nordic AB (Sweden)
Kungliga Tekcniska Hogskolan (Sweden)
2.6. Photonic metamaterials (PHOME)
Project description
Metamaterials are composite, man-made materials, composed of sub-wavelength metallic building
blocks, which show novel and unique electromagnetic properties, not occurring in natural materials. A
particularly important class of such materials is the negative refractive index metamaterials. Negative
refractive index metamaterials have been in the foreground of scientific interest in the last seven
years. In 2006-2007 near infrared and optical frequencies were obtained, despite the initial objections
and disbelief. However, many serious obstacles have to be overcome before the impressive
possibilities of optical/photonic metamaterials can become real applications. The present project
identifies the main obstacles and proposes specific approaches to deal with them; in addition, it
intends to study novel and unexplored capabilities of photonic metamaterials. Specifically, the project
objectives are the realization of 3D photonic metamaterials, the reduction of losses in photonic
metamaterials, the realization of active and tunable/switchable (electrically or optically) photonic
metamaterials by incorporating gain or nonlinearity, and the realization of chiral photonic
metamaterials. The accomplishment of those objectives is both a theoretical and a technological
challenge, as it requires proofs of concepts, advanced computational techniques and advanced
nanofabrication approaches. To guide and test the proposed photonic metamaterials, a number of
important and ICT relevant demonstrators have been demonstrated, which include thin-film optical
isolators, electro-optic modulators, optical switching, and negative refractive index material-based
"perfect lenses" in the infrared, and possibly in the visible. The implementation of the project will be
done through combined theory/modelling, fabrication and experimental testing efforts, in continuous
interaction. The broad theoretical and experimental expertise of the consortium, together with their
field shaping past contributions to metamaterials, make them capable to face the challenges involved
and to minimize the risk, ensuring the maximum possible success of the project.
Start date: 01/06/2008
End date: 31/05/2011
Funding organization: European Commission, FP7
Photonic structures studied: tuneable metamaterials
Project cost: 1.900.000 €
Participants:
17
Universitaet Karlsruhe (Germany)
Foundation for Research and Technology – Hellas (Greece)
Imperial College of Science, Technology and Medicine (United Kingdom)
Bilkent University (Turkey)
2.7. Optimal design and fabrication of electromagnetic metamaterials
for millimeter and microwave applications
Project description
In this proposal, a new class of artificial materials with prescribed electromagnetic properties, created
to a custom design via topology optimization and advanced multimaterial fabrication technologies is
proposed. These artificial materials, or meta-materials, are composites of dielectrics and magnetic
oxides, combined to produce new electromagnetic property tensors and previously unobtainable
figures of merit.
Unlike traditional antenna design approaches based on surface metallization (where an experienced
antenna designer can bypass formal design tools), exploitation of novel engineered material volumes
for antennas (and other RF applications) can only be realized with generalized design methodologies.
Topology optimization is such a method and allows for novel material microstructure and topology
designs from scratch.
The combination of powerful optimal design techniques with practical realization for specific
applications, will serve as a general example for a new approach for creating designed metamaterials,
useful for other functional materials. The new functionality of metamaterials will enable new
technology for several microwave and millimeter wave applications. The focus in this work will be the
design and fabrication of meta-materials for shrinking the size and increasing the functionality of
antennas such as large bandwidth and high gain.
By reducing size and adding functionality to a radiator element, avenues will be opened for many new
and practical phased array applications such as RF sensing, miniaturized transceivers and covert RF
tags to mention a few. This in turn will lead to cheaper configurations for the much smaller and
network-centric future systems.
Start date: 01/09/2006
End date: 31/08/2008
Funding organization: European Commission, FP7
Project Funding: 80.000 €
Participant:
Sabanci University (Turkey)
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2.8. Advanced computational studies of dynamic phenomena in
magnetic nano-materials
Project description
The opportunity to modify the excitation spectra in materials with modulated properties has stimulated
striving research activity in the area of artificial nanostructures with novel functionalities - so called
metamaterials. Magnetic materials with modulated properties also possess properties that cannot be
reduced to those of their constituents. The best example is the phenomenon of giant magneto-
resistance (GMR), the discovery of which was marked by the Nobel Prize in Physics for 2007. Similar
to photons in photonic crystals, the spectrum of magnons (spin waves) in periodic magnetic nano-
materials shows a tailored band structure. The latter consists of bands of allowed magnon states and
band gaps in which there are no allowed magnon states. By analogy to studies of other band-gap
materials, the field of research is called magnonics.
Further development and application of magnetic nano-structures requires a thorough understanding
of the relation between their physical and chemical structure and useful magnetic functionalities. The
ability to accurately predict properties of fabricated magnetic nano-structures and complete devices
theoretically would generate huge savings of resources, but remains illusive at present.
The goal of this project is to consolidate efforts of European researchers with a broad range of leading
expertise to create, to validate and to implement a flexible computational framework for modelling of
dynamics in realistic magnetic nano-materials and complete devices. The framework will be validated
via comparison of computational results against those obtained experimentally or using analytical
theories. We will model magnetic dynamics in topologically complex nanostructures, in view of
applying them in design of realistic devices. This project will provide a computational foundation for
creation of not only novel high speed magnetic technologies but also of those at interfaces with
photonics, plasmonics, phononics, and electronics.
Start date: 01/06/2009
End date: 31/05/2012
Funding organization: European Commission, FP7
Project cost: 1.170.976 €
Participants:
University of Exeter (United Kingdom)
Universita degli Studi di Ferrara (Italy)
University of Southampton (United Kingdom)
Uniwersytet Im. Adama Mickiewicza w Poznaniu (Poland)
19
2.9. Building radio-frequency identification solutions for the global
environment (BRIDGE)
Project description
Building Radio Frequency IDentification for the Global Environment (BRIDGE) is a European Union
funded 3-year integrated project addressing ways to resolve the barriers to the implementation of
RFID in Europe, based upon GS1 EPC global standards. Radio Frequency Identification (RFID) is a
technology which uses radiofrequency signals for automatic identification. Among the different
frequency bands that can be used for RFID, the one that is becoming a standard for supply chain
management is the UHF frequency band. The project consists of a series of business, technical
development and horizontal activities. Seven work packages have been set up to identify the
opportunities, establish the business cases and perform trials and implementations in various sectors
including anti-counterfeiting, pharmaceuticals, textile, manufacturing, re-usable assets, products in
service and retail non-food items. The project includes an important research and development
program in various aspects of RFID hardware, software, network and security. Within this immense
project, a work programme, named hardware development, includes developing tags using
metamaterials. Two main investigation topics are emphasized: developing miniaturized UHF tags
based on metamaterial geometries and and near field tags based on metamaterials.
Start date: 01/07/2006
End date: 01/07/2009
Funding organization: European Commission, FP6
Project cost: 7.5 million €
Participants:
CAEN (Italy)
UPM Raflatac (Finland)
Confidex (Finland)
Auto-ID Labs – Fudan University (China)
Auto-ID Labs – University of Cambridge (United Kingdom)
AT4 wireless (Spain)
AIDA centre – University of Catalonia (Spain)
Technical University of Catalonia (Spain)
2.10. Development and analysis of left-handed materials (DALHM)
Project description
Left-handed (LH) materials are composite materials with novel and unique electromagnetic properties,
which are not determined by the fundamental physical properties of their constituents but by the shape
and the distribution of specific patterns included in them. LH materials have the unique property of
having both the effective permittivity and the effective permeability negative. The aim of this project is
20
the theoretical understanding, analysis, development and testing of LH materials, and also the
investigation of their feasibility for commercial telecommunication applications. These applications
include RF absorbers, radomes, wide-angle impedance matching sheets for phased array antennas,
generation of nearly divergence-free RF beams, RF lenses, variable negative filters and remote
imaging.
The different objectives of the proposed effort are a better understanding of the physics of left-handed
(LH) materials, improving the existing modelling and simulation tools, with aim to study more
complicated structures than the structures which can be studied today, fabricating left-handed
materials (ordered and disordered) using various approaches, materials and processes, identifying
commercial telecommunication applications where such materials can make a big difference and
testing of the electromagnetic behaviour of these materials in the laboratory and in "relevant"
environments.
Start date: 01/09/2002
End date: 28/02/2006
Funding organization: N/C
Project cost: N/C
Participants:
Foundation for Research and Technology , Hellas (Greece)
Bilkent University (Turkey)
Imperial College of Science, Technology and Medicine (United Kingdom)
2.11. Electromagnetic and spin wave interactions in nanostructure-
based metamaterials and devices (EMSWIM)
Project description
The proposal is focused on the fundamental and applied research of electromagnetic and spin wave
processes in laterally patterned periodic nanostructures and derived metamaterials and devices, with
particular interest in magnetic materials. The research aims at the development and computer
implementation of a theoretical approach capable of modeling the electromagnetic response of the
nanostructures, their numerical and experimental investigation, proposing and designing novel
applications, and studying related physical phenomena such as photon-spin wave
interactions.Graphical, user-friendly software based on the numerical algorithm will be utilized for a
commercial scatterometric system in the frame of international collaboration with Dainippon Screen
Mfg. Co. Ltd., Japan. The project will use magneto-optical spectroscopy available at the host
institution and other optical, magneto-optical, and complementary magnetism- and surface-science
techniques provided by collaborating laboratories in the Czech Republic, Germany, and Japan. The
results obtained on the nanostructures will be used to propose and design novel artificial
metamaterials (such as magneto-photonic crystals) and devices (such as waveguides, microcavities,
polarizing, space-modulating and other optical filters).
21
Start date: 01/04/2008
End date: 31/03/2012
Funding organization: FP7
Project cost: 100000 €
Participant:
Charles University (Czech Republic)
2.12. Plasmonic cavity quantum electrodynamics with diamond-based
quantum systems (PLACQED)
Project description
This project aims to realize physical systems for the realization of plasmonic cavity quantum
electrodynamics using optically active diamond-based quantum systems such as atomic impurities.
Color centers in diamond provide a suitable test bed for applications of quantum information
processing, as well as selected spin-spin interactions. While there are hundreds of known color
centers in diamond, but only one (nitrogen vacancy) is studied extensively. The study will focus on
optical properties and identifying energy levels of alternative color centers both naturally occurring and
artificially implanted, potential candidates being Ni, Si, or Fe impurities. Research is lead in parallel on
solid-state-based cavity quantum electrodynamics with light confinement at sub-wavelength scale.
Using metal nanostructures and plasmons, the project aims at achieving individual or ensemble
strongly coupled emitter-cavity systems.
Start date: 01/08/2008
End date: 31/07/2013
Funding organization: FP7
Project Funding: 1.712.342 €
Participant:
University of Cambridge (United Kingdom)
2.13. Self-organized nanomaterials for tailored optical and electrical
properties (NANOGOLD)
Project description
The NANOGOLD project aims at the fabrication and application of bulk electro-magnetic
metamaterials. A promising new concept for the exploration of metamaterials is the use of periodic
structures with periods considerably shorter than the wavelength of the operating electromagnetic
radiation. This concept allows controlling the refractive properties. Making use of a bottom up
approach in materials design, self-organization of organic-inorganic composite materials containing
resonant entities will be applied. To tune electromagnetic properties, resonance and interference at
22
different length scales will be implemented. In such a way bulk optical metamaterials operating in
spectral domains appropriate for photonics will be obtained.
The groundbreaking solution to form such artificial matter is interdisciplinary and combines inorganic
chemistry, organic macromolecular synthesis, physics of electromagnetic resonances and liquid
crystal technology.
Start date: 01/08/2009
End date: 31/07/2012
Funding organization: FP7
Project Funding: 3.519.235 €
Participants:
Ecole Polytechnique Federale de Lausanne (Switzerland)
University of Hull (United Kingdom)
University of Sheffield (United Kingdom)
Ruprecht-Karls-Universitaet Heidelberg (Germany)
Universita della Calabria (Italy)
University of Patras (Greece)
Friedrich-Schiller-Universitaet Jena (Germany)
Virtual Institute for Artificial Electromagnetic Materials and Metamaterials (Belgium)
2.14. Nanochemistry and self-assembly routes to metamaterials for
visible light (METACHEM)
Project description
The objective of the METACHEM collaborative project is to use the extreme versatility of nano-
chemistry to design and manufacture bulk meta-materials exhibiting non-conventional electromagnetic
properties in the range of visible light. This spectral domain requires nano-scale patterns, typically
around 50 nm in size or less.
The consortium strategy consists in designing and synthesizing ad-hoc nano particles as optical
plasmonic nano-resonators and organising them through self-assembly methods in 2 or 3 dimensional
networks in order to produce dense highly ordered structures at a nano-scale level. Several
subprojects corresponding to different routes are proposed, all of them based on existing state-of-the-
art chemical and self assembly methods. In addition, the important issue of losses inherent to the
plasmonic response of the nano-objects is addressed in an original way by the adjunction of loss-
compensating active gain media.
A special effort is to be made on the difficult measurement of the non conventional meta-properties as
they constitute the first demonstration of the validity of the concept. A technological and an industrial
point are added towards the search of efficient, cost-effective and industrially feasible metamaterials.
23
Start date: 15/09/2009
End date: 14/09/2013
Funding organization: FP7
Project Funding: 3.699.990 €
Participants:
Centre National de la Recherche Scientifique (France)
Consiglio Nazionale delle Ricerche (Italy)
Université Catholique de Louvain (Belgique)
University of Manchester (United Kingdom)
Universita degli Studi di Siena (Italy)
Rhodia Laboratoire du Futur (France)
Teknillinen Korkeakoulu (Finland)
Universidad de Vigo (Spain)
Fraunhofer-Gesellschaft (Germany)
2.15. Optically controlled growth of nanotubes and nanowires (J2923
Optisch gesteuertes Wachstum von Nanoröhren und
Nanodrähten)
Project description
Description available only in German
Start date: 01/07/2009
End date: 30/06/2011
Funding organization: FWF Austria
Keywords: nanotubes, nanowires, spectroscopy, surface plasmon resonance, metamaterials,
nanophotonics
2.16. Resonance-domain metamaterials for sub-wavelength optics
Project description
Resonances play a crucial role in the optical properties of materials. Resonant transitions between
quantum states of atoms and molecules are responsible for absorption and refraction of light, while in
the macroscale, electromagnetic cavity resonances form the basis for lasers and other optical devices.
In the mesoscale, the optical response of atoms or molecules combined into nanoentities is
dramatically enriched by Mie-type resonances. As a result the optical properties of artificial materials
based on collection of nanoparticles in an appropriate matrix go beyond those of conventional
composites. Such materials typically consist of two- or three-dimensional (2D and 3D, respectively)
arrays of nanoparticles with subwavelength period and are often referred to as metamaterials. The
overall goal of the REDMETA Consortium is to develop resonance-domain metamaterials that will give
24
rise to unprecedented and advantageous optical properties due to the interplay between the Mie-like
resonances of individual particles and propagating modes of the structure. We expect that such
metamaterials will outperform conventional ones in (i) the tunability of spectral features; (ii) the ability
to form a desired local-field distribution and to use it for radiation control; and (iii) the magnitude of the
optical nonlinearity. The work will be based on a close collaboration between Prof. Yuri Svirko at the
Department of Physics of the University of Joensuu (UJ), Dr. Goëry Genty at the Nonlinear Optics
Group (NLO) at the Department of Physics of the Tampere University of Technology (TUT), and Dr.
Janne Simonen at the Optoelectronics Research Centre (ORC) of TUT. The Partners bring
significantly complementary expertise to the Consortium, which allows it to address unprecedented
questions regarding resonance-domain metamaterials. The immediate targets of REDMETA are
fundamental. However, it is expected that the fundamental results to be employed in the near future,
e.g., in the development of novel semiconductor light sources. The Consortium will pay special
attention to the protection of their results for possible exploitation. We expect the commercially viable
results to be transferred to industry through the network of spin-off companies around TUT and UJ, as
the Partner sites have successfully demonstrated earlier.The work also includes a significant
educational aspect. Several highly-qualified Ph.D.s with experience in experimental and highly
interdisciplinary research will be trained. The work will also contribute to the education of M.Sc.-level
scientists.
Funding organization: FinNano Finland
2.17. Metamaterials for photonics, high frequencies and optical
networks (Metamatériaux pour la photonique, les
hyperfréquences et l'optique des réseaux)
Project description
no description available
Funding organization: Programme national Nanosciences - Action concertée Nanosciences 2004,
France
2.18. Nonlinear Photonics with Metallic Nanostructures on Top of
Dielectrics and Waveguides
Project description
In this project we are going to investigate the optical properties of nanoscale mesoscopic metallic
nanostructures and of strongly correlated materials. We want to study both isolated and strongly
coupled nanoparticles. The optical properties are being investigated by continuous wave and by
ultrafast (femtosecond and picosecond) spectroscopy. Metallic nanoparticles are becoming an
important building block in nano-optics. However, in order to be able to localize light on a mesoscopic
25
scale, it will be necessary to understand the exact mechanism how light couples to such
nanostructures and how its energy is being transferred into electronic excitations (particle plasmons).
Furthermore, it is necessary to unterstand how these excitations can transfer to neighboring particles
and reradiate back into space. When arranging the particles into a regular metallic nano-structure, it
will be necessary to understand the linear and nonlinear optical properties of such metamaterials. Our
project aims to clarify the temporal dynamics and the control of light-matter coupling in metallic
nanostructures. Strongly correlated materials are believed to have the potential for the fastest optical
switches available. However, only a few experiments have so far proven the existence of theoretically
calculated quasiparticles in these systems, such as magnons and spinons. Nearly nothing is known
about the ultrafast temporal dynamics (lifetime and dephasing) of these quasiparticles. Our project
aims to investigate these elementary processes, using state-of-the art and novel ultrafast methods.
Funding organization: DFG Germany
Duration: Since 2004
Contact: Harald Giessen
Universität Stuttgart
4. Physikalisches Institut
Pfaffenwaldring 57
70569 Stuttgart
2.19. Analysis and Synthesis of resonant Antenna Structures based on
Metamaterials (Analyse und Synthese von resonanten
Antennenstrukturen basierend auf Metamaterialien)
Project description
Description available only in German
Funding organization: DFG Germany
Duration: 2005 until 2009
Contact: Ingo Wolff
Universität Duisburg-Essen
Fakultät für Ingenieurwissenschaften
Fachgebiet Allgemeine und Theoretische Elektrotechnik (ATE)
Bismarckstraße 81
47048 Duisburg
26
2.20. ZIK – Ultraoptics Project: Design and Implementation of
functional Metamaerials by Nanostructuring and Application of
those structures in Complex Photonic Systems (ZIK Ultraoptics -
Projekt: Design und Realisierung hochfunktioneller optischer
Metamaterialien durch Nanostrukturierung sowie deren
Anwendung in komplexen photonischen Systemen)
Project description
no description available
Funding organization: BMBF Germany
Duration: 01.04.2005 until 31.12.2010
2.21. METAMAT - 3D Photonic Metamaterials (METAMAT - Photonische
Metamaterialien - 3D-Metamaterialien)
Project description
no description available
Funding organization: BMBF Germany
Duration: 01.10.2008 until 31.09.2011
2.22. Applicable verification of hybrid eutectic systems for
metamaterials production
Project description
Investigation of different chemical compounds for metamaterials production.
Funding organization: Nauka Polska (Poland)
Start date: 01/01/06
End date: 04.12.06
Keywords: Metamaterial, eutectic structure
2.23. Production eutectic systems by “micro-pulling down”
Project description
Investigation of different chemical compounds for metamaterials production.
Funding organization: Nauka Polska (Poland)
Start date: 01/01/07
End date: 30/11/07
Keywords: Metamaterial, eutectic structure, TiO2, WO3, BaO, MnTiO3
27
2.24. Large area fabrication of 3D negative index metamaterials by
Nanoimprint Lithography (NIM_NIL)
Project description
Three-dimensional large area metamaterials, especially Negative Index Materials (NIMs) promise to
enable numerous novel and breakthrough applications like perfect lenses and cloaking devices, not
only but especially if they exhibit the desired properties in the visible frequency range. For the
European Photonics industry it is of paramount importance enabling fabricating such materials as
soon as possible, to maintain its important position in the areas of optical components and systems as
well as production technologies.
Till now such materials have not been produced, yet - neither in 3D nor on large areas, let alone both
combined. The aim of NIM_NIL is the development of a production process for 3D NIMs in the visible
regime combining UV-based Nanoimprint Lithography (UV-NIL) on wafer scale using the new material
graphene and innovative geometrical designs. This project will go beyond state-of-the-art in three
important topics regarding NIMs: the design, the fabrication using Nanoimprintlithography (NIL) and
the optical characterization by ellipsometry. New designs and the new material Graphene will be
investigated to extend the existing frequency limit of 900 nm into the visible regime. The fabrication
method of choice is UV-NIL since it allows cost efficient large area nanostructuring, which is
indispensible if materials like NIMs should be produced on large scale.
The negative refraction will be measured using ellipsometry which is a fast and non-destructive
method to control the fabrication process. At the end of the project a micro-optical prism made from
NIM will be fabricated to directly verify and demonstrate the negative refractive index. Each aspect of
innovation within NIM_NIL design, fabrication and characterization of NIMs is represented by experts
in this field resulting in a multidisciplinary highly motivated consortium containing participants from
basic research as well as industrial endusers from whole Europe.
Reference: 228637
Start date: 2009-09-01
Duration: 36 months
Project costs: 4.52 million euro
Project funding: 3.37 million euro
Participants:
SENTECH INSTRUMENTS GMBH, GERMANY
GESELLSCHAFT ZUR FOERDERUNG DER ANALYTISCHEN WISSENSCHAFTEN E.V., GERMANY
INSTITUT ZA FIZIKU, SERBIA
JENOPTIK POLYMER SYSTEMS GMBH, GERMANY
FRIEDRICH-SCHILLER-UNIVERSITAET JENA, GERMANY
MICRO RESIST TECHNOLOGY GESELLSCHAFT FUER CHEMISCHE MATERIALIEN SPEZIELLER
PHOTORESISTSYSTEME MBH, GERMANY
CONSIGLIO NAZIONALE DELLE RICERCHE, ITALY
FOUNDATION FOR RESEARCH AND TECHNOLOGY HELLAS, GREECE
UNIVERSITAET LINZ, AUSTRIA
28
2.25. NANOSTRUCTURED PHOTONIC METAMATERIALS
Project description
Over the last twenty years photonics, the science of light, has played a key role in creating the world
as we know it. Today it is impossible to imagine modern society without internet and mobile telephony
made possible by the implementation of optical fibre networks, CD's and DVD's underpinned by the
development of lasers, modern image display technologies, and laser-assisted manufacturing.
We believe that the next photonic revolution will continue to grow, explosively fuelled by a new
dependence on a radically different type of photonic materials called metamaterials. Metamaterials are
artificial electromagnetic media with unusual and useful functionalities achieved by structuring on a
sub-wavelength scale. Nanotechnology-enabled materials are now universally seen as the direction
where the global economy will grow strongly in the 21st century. The proposed Programme is at the
core of this global movement and focuses on an area of particular interest to the UK - nanophotonics
and metamaterials.
Our vision for this Programme is to develop a new generation of revolutionary switchable and active
nanostructured photonic media thus providing groundbreaking solutions for telecoms, energy, light
generation, imaging, lithography, data storage, sensing, and security and defence applications.
The Programme will mobilize and focus all of the resources and interdisciplinary expertise available at
the University of Southampton and with our collaboration partners in the UK and around the world, to
create a world-leading centre of research on Nanostructured Photonic Metamaterials.
The elements of adventure and key research challenges in this project can be summarized as follows:
we aim to develop photonic media allowing for ultra-high-density integration, the lowest possible
energy levels and the highest speeds of optical switching. This will be achieved by advancing the
physics of the control, guiding and amplification of light in nanostructures and by developing new
nanofabrication techniques and methods of hybridization and integration into the waveguide and fiber
environment of different novel metamaterial structures.
The main methodological paradigm for the Programme is to achieve new functionalities by developing
hybrid photonic metamaterials. The Programme will consist of strongly interlinked projects on
fabricating hybrid metamaterials, metamaterials as a platform for photonic devices and fundamental
physical experiments, controllable, switchable and active hybrid metamaterials, and developing new
ideas emerging from theoretical analysis.
Essential to the project will be the new world-leading 105M cleanroom and laboratory Mountbatten
complex at the University of Southampton.
This proposal is submitted on behalf of an internationally leading team with a formidable research
track record that within the last 10 years has led and participated in research projects with funding
exceeding 34 millions, published 463 journal research papers and given more than 200 invited talks at
major international meetings. The research will be developed in collaboration with key international
research groups and industrial laboratories and in this way form a "Global Laboratory" for the project.
This high-risk/high-reward Programme will be run by a strong Director-led management team which
will benefit from advice from an independent Project Mentor and Advisory Board. Strategic decisions
29
will be made using the "search-and-focus" approach involving regular critical reviews of the research
programme under an "active resources and risk management scheme" allowing for the redistribution
of resources and usage of reserves where they are most needed and to quickly foster new research
directions.
Funding organization: EPSRC UK
Start date: 01 July 2009
End date: 30 June 2015
Project funding: 5,202,355 £
2.26. Active Plasmonics and Lossless Metamaterials
Project description
Metal surfaces can support so called surface plasmons, density waves of free electrons. These
plasmon waves can interact with light, opening the way to a novel area of optics, namely plasmonics.
When the metal surface is nanostructured, a possibility for true nanoscale optics emerges. In this work
we aim to alleviate or even remove the unavoidable absorption losses caused by the metal by
amplifying the plasmon waves with semiconductor quantum wells and dots, thus demonstrating low-
loss plasmonic components. They will be designed by novel electromagnetic simulation methods
developed during the project, running on a supercomputer cluster. We will also use this approach to
design and fabricate novel wide-band low-loss or even lossless metamaterials, highly promising
structures with a negative refractive index that can for example slow or even stop incoming light
pulses.
Funding organization: EPSRC UK
Start date: 01 July 2009
End date: 30 June 2012
Project funding: 340,868 £
2.27. Advanced Design and Control of Active and Passive
Metamaterials : from Microwaves
Project description
Light usually passes through transparent materials in simple ways that science pupils learn at school.
However, physicists have recently been examining the possibility of taking a normal transparent
material, and inserting tiny metallic inclusions in various shapes and arrangements. As the light
passes over these structures tiny currents are set up that generate electric and magnetic fields that
modify the way the light travels through the material. The effects can be dramatic leading to slowing
light to a few metres per second, or to bending light in very unusual ways / so-called negative
refraction. These effects are potentially very useful in all kinds of ways that are only beginning to be
understood. Lenses that break traditional diffraction limits are one possibility. An 'invisibility cloak'
another. At the more mundane level, the wavelengths that we will be focussing upon (mm) are
30
expected to enhance the performance of cellular telephone networks, designed to handle large area,
mobile applications personal communication services/networks, global positioning systems, broadcast
satellite television, satellite phone services and automotive electronics. Waves in this part of the
spectrum have a fabulous information capacity. The highly directive nature of mm-wave beams, the
predicted small size and lightweight of the hardware are also great advantages. The main desire is to
unify more than one function in an application (e.g. antenna/filter/generator or amplifier). The progress
towards higher frequencies, coupled to miniaturization, increases the bandwidth and information
capacity. The metallic inclusions are much smaller than the wavelength of light so that as far as the
light is concerned the material with inclusions behaves as a uniform effective medium, or a meta-
material. The research is therefore a concerted theoretical platform activity aimed at creating the best
design and understanding of metamaterials obtained so far. We will be focussing on design solutions
that will address some of the known problems associated with metamaterials as well as others not
known at this stage. Loss is a major issue that we will address through the design of metallic
inclusions that are actively controlled by applying external currents.
Salford will address loss control and elimination by using active diode additions to traditional ring and
omega particle structures. Chiral, or handed, inclusions will provide smart artificial molecules that are
expected to have completely new properties. These expectations will require new and deeper insights
into the equations that describe how electromagnetic fields interact with matter, and so will be
extended to embrace the ideas of nonlinearity (i.e. output is not proportional to input) and nolocality
(memory).
Surrey will adopt a specific modelling approach that will bridge the gap between methods used at the
microscopic nanomaterials level and techniques previously used for macroscopic multilayered
structures. They will examine ordered/disordered arrays of inclusions as conceived by Salford.
Surrey will pursue new ideas of using metamaterials to slow down light that rely on geometry rather
than resonance effects. Imperial will address fundamental aspects related to plasmonics. Issues of
definition also need to be addressed so that our codes will be written with the utmost robustness and
reliability.
Funding organization: EPSRC UK
Start date: 15 August 2007
End date: 14 August 2010
Project funding: 332,058 £
2.28. Negative index metamaterials for visible-light optics
Project description
Recent advances in nanofabrication allow one to create new composite metamaterials with
constituents of different forms and sizes down to nanoscales. These materials have attracted
considerable interest as they offer a possibility to realise a negative index of refraction with many
surprising properties important for optics, communication and electronics. Nanocomposite
metamaterials also promise a whole variety of amazing applications, e.g., a perfect lens producing a
31
perfect image of an object, a nanolens focusing light into a sub-wavelength spot, a nanolaser
amplifying near-fields through a stimulated emission of radiation.
We have recently designed and nanofabricated the first artificial metamaterial with negative index of
refraction at visible-light frequencies. In this material the high frequency magnetic response is
produced by collective oscillations of electrons in coupled pairs of gold nanopillars. We have
confirmed the extraordinary properties of the new media by observing the impedance matching effect
(previously known only for radio-wave frequencies) and a large enhancement of the electric field in the
immediate proximity of individual nanomolecules. It was only the relatively large dissipation and small
thickness of the fabricated nanocomposites that did not allow us to observe the effect of negative
refraction.
This proposal aims to expand our initial findings into a viable research programme based on our
current competitive advantage in exploration of negative index metamaterials. We will design
composite nanomaterials made from coupled metallic nanoelements with stronger magnetic and
electric response at frequencies of visible light. The main focus of our research will be engineering of
negative index materials with low dissipation, which is a key element to developing new optical
devices including the perfect lens. We plan to fabricate new optical composite nanomaterials, study
their extraordinary electromagnetic properties and assess some of their applications, which we believe
are the most promising and within our expertise (feasibility study of a perfect lens and a nanolens,
biosensing, etc.).
Funding organization: EPSRC UK
Start date: 12 February 2007
End date: 11 February 2010
Project funding: 468,874 £
2.29. Building Ceramic Metamaterials from Nanoparticles: A combined
Modelling, Tomography and In-situ Loading Study
Project description
Materials characterization is crucial for the quantification and prediction of their physical, chemical and
mechanical properties: Molecular simulation has provided experiment with unique insight and
prediction for over 60 years. However, new (nano)materials are being synthesized with ever
increasing structural complexity and it may soon prove impossible to generate models that are
sufficiently realistic to describe them adequately.
Molecular simulations proceed by using the symmetry of the system, together with the coordinates of
the basis atoms to generate a crystallographic array, periodic in three dimensions.
Here, we pioneer a new systematic approach to prescribe the structure of a nanomaterial. Specifically,
a simulation code will enable the systematic generation of a nanostructure by exploiting the space
symmetry of the nanomaterial and positioning nanoparticles, rather than atoms, at basis positions;
32
molecular dynamics will be used to enable the nanobuilding blocks to formulate the walls of the
nanomaterial.
In parallel, experiment (bottom up) will be used to synthesise nanoparticles including their self-
assembly into order-connected and disordered-connected superstructures. Top down approaches to
fabricate nanoscale architectures will be achieved by focused field-emission electron beams, which
will drill nanoarchitectures into single crystals with sub 10nm resolution.
Central to the experimental work will be the verification and validation of the modelling process. One
key-technology, which can resolve areas deep within the nanostructure, is nanotomography. Here
tomographic techniques in the transmission electron microscope (TEM) will be used to map the 3D
elemental distribution and 3D morphology (faceting distribution) such that quantitative parameters,
including connectivity and surface area can be extracted. This 3D metrology data will be compared
directly to the modelling predictions. Tomographic techniques will be used to characterise the
metamaterials in three-dimensions and will not only provide unprecedented insight into the structural
architectures deep within the nanomaterials, but also provide essential validation for the atomistic
models.
Equipped with (validated) structural models, mechanical properties, such as Youngs modulus, elastic
constants will be calculated and stress-strain curves simulated together with chemical properties,
including surface reactivity (catalysis, sensor) and ionic transport (fuel cells, rechargeable batteries).
Nanomechanical testing: Innovative in-situ nanoscale mechanical deformation tests with local force
determination using Sheffield's In-Situ TEM NanoLAB facility will be used to measure the mechanical
properties. This will provide fundamental insight into the engineering rules at the nanoscale and
validate the mechanical property simulations.
Compression and tensile testing in the specimen chamber of a TEM we will extract key-parameters on
mechanical elastic and plastic properties, which will be compared with modelling predictions.
Mechanical tests provide a stringent test of the model because they will necessarily be influenced by
the structure on all three hierarchical levels of complexity - polymorphic structure, micro-structure
(grain-boundaries, dislocations, point defects) and nanostructure.
Once the simulated properties have been validated, they will be used predictively:
Correlation tables will be constructed to explore how the nano(structure) influences the properties.
We propose that the flawless nature in synergy with the architecture of entirely near-surface
nanomaterials will proffer unique mechanical and chemical properties. For the bulk analogue, defects -
such as impurities, inclusions, dislocations and twin boundary generation mechanisms provide
vehicles for fracture and plastic collapse. Conversely, a nanomaterial, with no such defective
microstructure and restrictive dislocation mechanics, will sustain remarkable loadings.
Funding organization: EPSRC UK
Start date: 01 November 2009
End date: 31 October 2012
Project funding: 265,403 £
33
2.30. NANOSTRUCTURED METAFILMS: A NEW PARADIGM FOR
PHOTONICS
Project description
The proposed research introduces a special type of metamaterials, namely planar metamaterials (or
metafilms), for practical photonic applications. As a result, a whole new class of extremely compact
(low-dimensional) photonic devices that replace the existing bulk optical components (such as spectral
filters, polarizers, waveplates, beam splitters etc.) is envisaged. But more importantly artificial planar
media allows achieving exotic photonic functionalities (e.g. optical superconductor, asymmetric
transmission) that are hardly possible with the use of conventional bulk optical materials. Moreover,
the research aims to add a new dimension to the concept of planar metamaterials, and therefore
dramatically expand the range of available photonic functionalities, by combining electronic/molecular
response of media and metamaterial resonances due to structuring.
Funding organization: EPSRC UK
Start date: 01 October 2008
End date: 30 September 2013
Project funding: 592,915 £
34
3. Literature survey
3.1. Overview of publications
Publications on metamaterials have increased exponentially during last 7 years. In the
figures below is shown the number of papers on metamaterials as well as in their different
main applications (source: ISI Web of Knowledge)
Papers published on Metamaterials (source: ISI Web of Knowledge)
0
200
400
600
800
1000
1200
1400
1600
1800
2000
2001 2002 2003 2004 2005 2006 2007 2008
Metamaterials
Figure 1 Papers published on Metamaterials over the period 2001-2008 (source: ISI Web of
Knowledge)
Papers published on Cloaking
(source: ISI Web of Knowledge)
0
10
20
30
40
50
60
2006 2007 2008 2009
Cloaking
Figure 2 Papers published on Cloaking over the period 2006-2009 (source: ISI Web of
Knowledge)
35
Papers published on Negative-index
(source: ISI Web of Knowledge)
0
50
100
150
200
250
300
350
400
2001 2002 2003 2004 2005 2006 2007 2008
Negative-index
Figure 3 Papers published on Negative-index over the period 2001-2008 (source: ISI Web of
Knowledge)
Papers published on Superlenses
(source: ISI Web of Knowledge)
0
5
10
15
20
25
30
35
40
45
50
2002 2003 2004 2005 2006 2007 2008
Superlenses
Figure 4 Papers published on Superlenses over the period 2002-2008 (source: ISI Web of
Knowledge)
As it can be seen on the top figure, only a few papers were published at the beginning of the 2000s
while over 1800 articles could be found for the year 2008. It is worth to note the increasingly
importance of some phenomena as inherently linked to metamaterials nanostructures such as
cloaking, optical negative index metamaterials, and superlenses since 2008, showing the recent
interest aroused by the latest developments and improvements in this area of photonics.
36
3.2. Metamaterial antennas
The idea of using metamaterials for fabrication of antennas was first explained by Ziolkowski [1] and
Guarnero [2] in 2001 when reporting a material with negative electrical permittivity and negative
magnetic permeability.
In 2002, Enoch et al. presented a metamaterial for directive emissions [3]. In this case the
metamaterial is not a split-ring resonator but made of several layers of a metallic mesh of thin wires
(with wires in the three directions of space) and slices of foam. Interestingly the permittivity of this
material, above the plasma frequency can be positive and less than one. This means that the
refractive index is less than one, but hardly above zero. In this case, the relevant parameter is often
the contrast between the permittivities rather than the permittivity itself. This occurs because the
equivalent permittivity has a behavior governed by a plasma frequency in the microwave domain. This
low optical index material then becomes a good candidate for creation of extremely convergent
microlenses. Wu et al. [4] confirmed the analysis of Enoch and his group by using commercially
available software to simulate the radiation of an antenna embedded in a metamaterial substrate.
Alici and Özbay investigated in 2006 the possibility of using metamaterials to enhance the radiated
power of antennas [5]. According to both investigators, materials which can produce negative
permeability could possibly allow for properties such as an electrically small antenna size, high
directivity, and tunable operational frequency. They demonstrated that a SRR composite behaves like
an electrically small antenna (λ/10) operating at the resonance frequency of the SRR. This antenna
can be used instead of the planar patch antennas in some applications. Secondly, by introducing
multi-SRRs beam direction shifts can be observed. The authors believe that this property might lead to
steerable antennas that are composed of SRRs.
Eleftheriades and Balmain described metamaterial antennas employing negative refractive index
transmission-line metamaterials (NRI-TLM) [6]. These include lenses that can overcome the diffraction
limit, small-band and broad-band phase shifting lines, small antennas, low-profile antennas, antenna-
feed networks, novel power architectures, and high-directivity couplers. A novel approach for
implementing NRI-TLM is loading a planar metamaterial network of transmission lines with series
capacitors and shunt inductors, which has a higher performance than standard transmission lines.
This results in a large operating bandwidth while the refractive index is negative. Because super-
lenses can overcome the diffraction limit, this allows for a more efficient coupling to the external
radiation, and enables the availability for a broader band of frequency.
The development of metamaterial antennas has been so important over the past few years that
Rayspan, an American company funded in 2006, currently offers commercially-available antennas
made of metamaterials [7]. The company recently reported the sale of 20 million antennas since its
creation in 2006. According to their webpage, their ultra-compact antennas offer superior
37
communication speed, range and mobility than standard antennas. Their product is therefore suited
for wireless communication systems. For example, Rayspan provides, among others, Netgear with a
wireless gigabit router providing twice the bandwidth with less interference. The internal metamaterial
antennas are fine-tuned for each frequency band, delivering maximum range more than doubling the
throughput.
[1] R. W. Ziolkowski, “Superluminal transmission of information through an electromagnetic
metamaterial,” Phys. Rev. E 63 (4), 046604 (2001)
[2] S. Guarnero, “Metamaterial – material engineering inverts the classic laws of physics,”
Electtronica Oggi 306, 76 (2001)
[3] S. Enoch, G. Tayeb, P. Sabourouz, N. Guerin, and P. Vincent, “A metamaterial for directive
emission,” Phys. Rev. Lett. 89 (21), 213902-1 (2002)
[4] B.-I. Wu, W. Wang, J. Pacheco, X. Chen, T. Grzegorczyk, and J. A. Kong, “A study of using
metamaterial as antenna substrates to enhance gain,” Progress in Electromagnetic Research 51
295 (2005)
[5] K. B. Alici, and E. Özbay, “Radiation properties of a split ring resonator and monopole composite,”
Phys. Stat. Sol. 244 (4), 1192 (2007)
[6] G. V. Eleftheriades, and K. G. Balmain, Negative Refraction Metamaterials: Fundamental
Principles and Applications, John Wiley, New Jersey (2005)
[7] www.rayspan.com
3.3. Cloaking
The possibility of using cloaking devices is recent, at least in terms of scientific research. The idea is
to develop materials that would allow objects to be invisible in some frequency ranges of the
electromagnetic spectrum.
The first demonstration of such a concept was performed by Schurig et al. In 2006 [1]. This group from
Duke University showed that a copper cylinder was hidden inside a cloak made of artificially-designed
metamaterial structure designed for operating in the microwave frequency range. Using a geometrical
transformation, they demonstrated that the material properties (ε and μ) were dependent on the
geometry of the cloak. Split-ring resonators, tailored to match the desired conditions, had the 3mm-
side squared-shape of thickness 0.2mm. The square’s edges were rounded (with a radius r) and the
square, instead of being closed, was terminated by two arms of length s directed towards the centre of
the square [1]. The two parameteres r and s were modified as a function of the cylinder’s radius.
Some physical insights on the cloaking technique were given by Alù and Engheta [2,3]. They
explained how the use of homogeneous isotropic plasmonic and metamaterial covers may drastically
reduce the scattered field from 3D impenetrable objects of dimensions comparable with the
wavelength, effectively providing a cloaking technique. Full-wave simulations and animations of the
38
mechanism underlying this cloaking effect (when a conducting or highly plasmonic object is to be
cloaked) were provided. The results reported clearly show how the “anti-phase” scattering properties
of properly designed plasmonic covers may be effective in making transparent conducting, plasmonic,
as well as dielectric objects of dimensions comparable with the operating wavelength. This technique
relies on metamaterials with homogenous and isotropic properties and it can be easily applied to fully
3D objects. Using different numerical examples, Alù and Engheta also showed how the sensitivity to
the geometrical parameters, shape, frequency or presence of losses is relatively weak in this scheme,
since it does not rely on any resonant effect. This is believed to be a clear advantage in practical
situations.
The same group developed the idea of employing plasmonic covers to cloak an isolated conducting,
plasmonic or insulating sphere through scattering cancellation [4] and extended this concept by
investigating the possibility of cloaking multiple objects placed in close proximity of each other, or even
joined together to form a single object of large electrical size. It was shown how the coupling among
the single particles, even when placed in the very near zone of each other, is drastically lowered by
the presence of suitably designed covers, thus providing the possibility of making collections of objects
transparent and “cloaked” to the impinging radiation even when the total physical size of the system is
sensibly larger than the wavelength. Numerical simulations and animations were presented to validate
these results and give further insights into the anomalous phenomenon of transparency and cloaking
induced by plasmonic materials and metamaterials.
Following the work by Alù and Engheta, Kanté et al. proposed an electromagnetic cloak, which
exploits the electric response of gold split-ring resonators instead of their magnetic response [5].
Numerical simulations performed at infrared frequencies (f=100THz) reveal low loss and weak
impedance mismatch, therefore proving the interest in using SRRs as a basic structure for the design
of metamaterials. The group also showed that SRRs can be ultimately replaced by simple cut wires for
the construction of approximate electromagnetic cloaks whose dielectric permittivity is the only
parameter varying with space coordinates.
Another possible design for a cloak uses transformation optics, in which a conformal coordinate
transformation is applied to Maxwell’s equations to obtain a spatially distributed set of constitutive
parameters that define the cloak. Recently, Liu et al. presented an experimental realization of a cloak
design that conceals a perturbation on a flat conducting plane, under which an object can be hidden
[6]. To match the complex spatial distribution of the required constitutive parameters, a metamaterial
consisting of thousands of elements was constructed, the geometry of each element determined by an
automated design process. The so-called “ground-plane cloak” was realized with the use of non-
resonant metamaterial elements, resulting in a structure having a broad operational bandwidth
(covering the range of 13 to 16 gigahertz in our experiment) and exhibiting extremely low loss. The
experimental results obtained indicated that this type of cloak should scale well toward optical
wavelengths.
39
[1] D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith,
“Metamaterial electromagnetic cloak at microwave frequencies,” Science 314, 977 (2006)
[2] A. Alù, and N. Engheta, “Plasmonic materials in transparency and cloaking problems: Mechanism,
robustness and physical insights,” Opt. Express 15 (6), 3318 (2007)
[3] M. G. Silveirinha, A. Alù, and N. Engheta, “Parallel-plate metamaterials for cloaking structures,”
Phys. Rev. E 75, 036603 (2007)
[4] A. Alù, and N. Engheta, “Achieving transparency with plasmonic and metamaterial coatings,”
Phys. Rev. E 72, 016623 (2005)
[5] B. Kanté, A. de Lustrac, J.-M. Lourtioz, and S. N. Burokur, “Infrared cloaking based on the electric
response of split ring resonators,” Opt. Express 16 (12), 9192 (2008)
[6] R. Liu, C. Ji, J. J. Mock, J. Y. Chin, T. J. Cui, and D. R. Smith, “Broadband ground-plate cloak,”
Science 323, 366 (2009)
3.4. Superlenses
A superlens is a lens capable of subwavelength operation. Unlike classical optical lenses,
superlenses’ resolution is not restricted by the diffraction limit, therefore allowing for
magnification of near field rays. This new type of optical lens was first described by John
Pendry in 2000 [1]. In this paper, Pendry identified the capacity of imaging subwavelength-
dimension objects such as atoms as the main limit of standard optical lenses. Using a slab of
negative refractive index material, he demonstrated that all Fourier components of a two-
dimension image can be focused. Showing that the evanescent field decay can be cancelled
using this so-called meta-material, he deduced that both propagating and evanescent waves
contribute to the resolution of the image. This conclusion leads to the possibility of perfect
reconstruction of image through the lens beyond practical limitations of aperture and
perfection of lens surface. Although this demonstration could have been made independently
from the development of metamaterials, it would have been of no interest without the
possibility of fabricating such a device, as emphasized by Pendry. However, using results
given by Sievenpiper et al. [2], and Pendry et al. [3] who demonstrated that wire structures
with lattice spacings of the order of a few millimeters behave like a plasma with a resonant
frequency, ωep, in the GHz region. Using such structure at a frequency ω<ωep allows the
dielectric response to be negative. It was also demonstrated by Pendy et al. [4] as well as
Smith et al. [5], that a structure containing loops of conducting wires has properties similar to
magnetic plasma allowing the permeability of the structure to be negative at some
frequencies. Using these different results, Pendry [1] demonstrated the possibility of
40
producing a structure closely approaching the conditions: ε = -1 and μ = -1. Simulations
showed that a version of that superlens operating in the visible region of the electromagnetic
spectrum (λ=356nm) could be realized in the form of a thin slab of silver, allowing the
resolution of objects of only few nanometers. Such a result represents a milestone to the
fabrication of perfect optical lenses such as the one described by Pendry.
In 2005, two different groups experimentally verified the results demonstrated by Pendry five years
earlier. Fang et al. [6] demonstrated sub–diffraction-limited imaging with 60-nanometer half-pitch
resolution, or one-sixth of the illumination wavelength (λ=356nm). By properly designing the thickness
of silver that allows access to a broad spectrum of subwavelength features, they also showed that
arbitrary nanostructures can be imaged with good fidelity. The objects were placed about 40 nm away
from the 35-nm silver film, and imaged onto a photoresist on the other side of the silver film under
ultraviolet (UV) illumination (at a wavelength of 365 nm). Using focused-ion beam lithography, the
chrome objects were patterned on quartz and then planarized, using a 40-nm-thick layer of polymethyl
methacrylate (PMMA). The word “NANO” written with a linewidth of 40nm was imaged using the
fabricated silver lens. Similarly, Melville and Blaikie [7] used extremely flat (roughness of 1nm) 50nm-
thin films of silver to image gratings with different periods (from 500nm down to 40nm) illuminated with
a mercury lamp (λ=356nm). The fabrication of the superlens was done by conformal-mask
photolithography. Tungsten masks were patterned onto a conformable glass substrate using electron-
beam lithography followed by the deposition of additional dielectric spacer and silver lens layers. The
finished masks were then brought into vacuum contact with a resist stack for lithographic exposures.
The first dielectric layer had two functions: providing a means of spacing the silver from the mask, and
planarizing the tungsten mask to smooth out the uneven topology before the silver lens layer is
deposited. This planarization was critical to the experiment, as if there was significant topography
transferred through to the silver then any images that result may have been caused by this instead of
the desired planar lensing property.
[1] J. B. Pendry, “Negative refraction makes a perfect lens,” Phys. Rev. Lett. 85 (18), 3966 (2000)
[2] D. F. Sievenpiper, M. E. Sickmiller, and E. Yablonovitch, “3D wire mesh photonic crystals,” Phys.
Rev. Lett. 76, 2480 (1996)
[3] J. B. Pendry, A. J. Holden, D. J. Robbins, and W. J. Stewart, “Low frequency plasmons in thin-wire
structures,” J. Phys. Condens. Matter 10, 4785 (1998)
[4] J. B. Pendry, A. J. Holden, D. J. Robbins, and W. J. Stewart, “Magnetism from conductors and
enhanced non-linear phenomena,” IEEE Trans. Microwave Theory Tech. 47, 2075 (1999)
[5] D. R. Smith, Willie J. Padilla, D. C. Vier, S. C. Nemat-Nasser, and S. Schultz, “Composite medium
with simultaneously negative permeability and permittivity,” Phys. Rev. Lett. 84, 4184 (2000)
[6] N. Fang, H. Lee, C. Sun, and X. Zhang, “Sub-diffraction-limited optical imaging with a silver
superlens,” Science 308, 534 (2005)
41
[7] D. O. S. Melville, and R. J. Blaikie, “Super-resolution imaging through a planar silver layer,” Opt.
Express 13 (6), 2127 (2005)
3.5. 3.5 References
In order to complete the information gathered by the previous description, a list of the most
remarkable publications on metmaterials is given below. Most of the information summarized in this
report, and not referenced in the previous sections, has been based on these publications.
[1] R. N. Bracewell, Wireless Eng. 31, 320 (1954)
[2] W. Cai, U. K. Chettiar, A. V. Kildishev, and V. M. Shalaev, “Designs for optical cloaking with
high-order transformations,” Opt. Express 16 (8), 5444 (2008)
[3] C. Caloz, and T. Itoh, Electromagnetic Metamaterials: Transmission Line Theory and Microwave
Applications, Wiley-IEEE Press, New Jersey, USA, (2005)
[4] X. L. Chen, et al., Phys. Rev. B 72, 113111 (2005)
[5] Y. F. Chen, et al., Phys. Rev. Lett. 95, 067402 (2005)
[6] G. Dolling, et al., Opt. Lett. 30, 3198 (2005)
[7] T. Driscoll, et al., Appl. Phys. Lett. 88, 081101 (2006)
[8] N. Engheta, and R. W. Ziolkowski, Electromagnetic Metamaterials: Physics and Engineering
Explorations, Wiley-IEEE Press, New Jersey, USA, (2006)
[9] C. Enkrich, et al., Phys. Rev. Lett. 95, 203901 (2005)
[10] S. Foteinopoulou, et al., Phys. Rev. Lett. 90, 107402 (2003)
[11] N. Garcia, and M. Nieto-Vesperinas, Opt. Lett. 27, 885 (2002)
[12] A. Grbic, and G. V. Eleftheriades, Phys. Rev. Lett. 92, 117403 (2004)
[13] C. L. Holloway, et al., IEEE Trans. Antennas Propagat. 51, 2596 (2003)
[14] A. A. Houck, et al., Phys. Rev. Lett. 90, 137401 (2003)
[15] J. Li, and J. B. Pendry, “Hiding under the carpet: a new strategy for cloaking,” Phys. Rev. Lett.
101, 203901 (2008)
[16] Z. Q. Li, et al., Appl. Phys. Lett. 86, 223506 (2005)
[17] Z. Q. Li, et al., Nano Lett. 6, 224 (2006)
[18] S. Linden, et al., Science 306, 1351 (2004)
[19] P. F. Loschialpo, et al., Phys. Rev. E 67, 025602 (2003)
[20] W. T. Lu, et al., Phys. Rev. E 69, 026604 (2004)
[21] C. Luo, et al., Phys. Rev. B 65, 201104 (2002)
[22] J. Pacheco, et al., Phys. Rev. Lett. 89, 257401 (2002)
[23] W. J. Padilla, et al., J. Opt. Soc. Am. B 23, 404 (2006)
[24] W. J. Padilla, et al., Phys. Rev. Lett. 96, 107401 (2006)
[25] W. J. Padilla, et al., Materials Today 9, 7 (2005)
[26] C. G. Parazzoli, et al., Phys. Rev. Lett. 90, 107401 (2003)
[27] P. V. Parimi, et al., Nature 426, 404 (2003)
42
[28] J. B. Pendry, and D. R. Smith, Phys. Rev. Lett. 90, 029703 (2003)
[29] J. B. Pendry, et al., Phys. Rev. Lett. 76, 4773 (1996)
[30] A. Pimenov, et al., Phys. Rev. Lett. 95, 24700949 (2005)
[31] D. Schurig, et al., Appl. Phys. Lett. 88, 041109 (2006)
[32] V. M. Shalaev, et al., Opt. Lett. 30, 3356 (2005)
[33] R. A. Shelby, et al., Science 292, 77 (2001)
[34] C. M. Soukoulis, et al., Science 47, 315 (2007)
[35] T. Timusk, and P. L. Richards, Appl. Opt. 20, 1355 (1981)
[36] R. Ulrich, Infrared Phys. 7, 37 (1966)
[37] P. M. Valanju, Phys. Rev. Lett. 88, 187401 (2002)
[38] M. S. Wheeler, et al., Phys. Rev. B 73, 045105 (2006)
[39] M. C. K. Wiltshire, et al., Science 291, 849 (2001)
[40] T. J. Yen, et al., Science 303, 1494 (2004)
[41] S. Zhang, et al., Phys. Rev. Lett. 95, 137404 (2005)
[42] S. Zhang, et al., Phys. Rev. Lett. 94, 37402 (2005)
[43] J. Zhou, et al., Phys. Rev. Lett. 95, 223902 (2005)
[44] Issue about Focus on Negative Refraction, New J. Phys. 7 (2005)
[45] Issue about Focus on Metamaterials, J. Opt. Soc. Am. B 23 (2006)
4. Current applications
In this chapter, the results of a patent search performed on http://ep.espacenet.com for the
search terms listed below is given.
Keywords: metamaterials, metamaterial, cloaking
4.1. Information and Communication Technologies
4.1.1 Optical interconnect devices and structures based on metamaterials - US
2008212921 (A1)
Summary
Improved optical interconnect devices, structures, and methods of making and using the devices and
structures are provided. The optical interconnect devices, which can be used to connect components
or route signals in an integrated-circuit or circuits, generally include an optical element having a
metamaterial with a negative index of refraction. The optical element is configured to receive an
optical signal from a first component and transmit the optical signal to a second component. Each
43
interconnect device or structure can be fabricated to have a small size and complex functionalities
integrated therein. Other embodiments are also claimed and described.
4.1.2 Negative-refraction metamaterials using continuous metallic grids over
ground for controlling and guiding electromagnetic radiation - US
2008204164 (A1)
Summary
For the cost effective implementation of negative-index refraction, an anisotropic hyperbolic planar
metamaterial comprising a first set of substantially parallel, unloaded and coplanar transmission lines
(being spaced with a periodicity dy), a second set of substantially parallel, unloaded and coplanar
transmission lines, (being spaced with a periodicity dx), further being coplanar and substantially
orthogonal with the first set of transmission lines, wherein the periodicities of first set and second set
of transmission lines being governed by the following relationship:
2)()( dyfdxf yx
where βx and βy are the intrinsic propagation constants of electromagnetic waves of frequency f
propagating along the first and second set of transmission lines, respectively.
4.1.3 Use of left-handed metamaterials as a display, particularly on a hob, as
well as display and display method - US 2007267406 (A1)
Summary
Coatings with left-handed metamaterials, which are man-made materials comprising microstructures
having unusual electro-magnetic properties, are provided around an appliance, such as a hotplate or
hob, incorporating induction heating coils that functions as an optical display. In one embodiment,
operation of induction heating coils in the cook top alters the optical properties of the metamaterial.
Therefore, if the metamaterials were previously transparent, they may become opaque. Doing so
changes the display, which can be detected by an operator. This makes possible creating an
automatic operating display for an appliance, such as an induction based hob.
4.1.4 Nonlinear optical devices based on metamaterials - WO 2007133727 (A1)
Summary
This patent describes an apparatus including one or more optical couplers, an optical medium, and an
optical pump source. The optical medium behaves as a negative refractive index material over a
frequency range. The one or more optical couplers are configured to provide first and second optical
inputs to the optical medium and to provide an optical output from the optical medium. The optical
pump source is coupled by one of the one or more optical couplers to deliver pump light to the optical
medium.
44
4.1.5 Antennas, devices and systems based on metamaterial structures - US
2008258981 (A1)
Summary
In this patent, techniques, apparatus and systems that comprise one or more composite left
and right handed metamaterial structures in processing and handling electromagnetic wave
signals are presented. Antenna, antenna arrays and other RF devices can be formed based
on composite left and right handed metamaterial structures. The described composite left
and right handed metamaterial structures can be used in wireless communication RF front-
end and antenna sub-systems.
4.1.6 Metamaterial antenna arrays with radiation pattern shaping and beam
switching - US 2008258993 (A1)
Summary
This invention describes several apparatus, systems and techniques for using composite left and right
handed metamaterial structure antenna elements and arrays to provide radiation pattern shaping and
beam switching.
4.1.7 Single-Feed Multi-Cell Metamaterial Antenna Devices
US2009251385 (A1)
Summary
In this patent designs and techniques of composite right-left handed (CRLH) metamaterial antenna
devices are presented, including CRLH metamaterial devices that comprise metamaterial cells formed
on a substrate and a conductive launch stub formed on the substrate to be adjacent to each of the
metamaterial cells and electromagnetically coupled to each of the cells.
4.1.8 Tunable delay system and corresponding method - WO 2008116289 (A1)
Summary
The present invention relates to a tunable delay system and corresponding method for delaying a
signal. The system includes an oscillator for providing a carrier and a first mixer modulates the signal
with the carrier. The modulated signal is delayed in a metamaterial transmission line. Afterwards, a
second mixer is used to separate the delayed signal from the carrier. This invention also relates to
using a metamaterial transmission line for delaying a modulated signal.
45
4.1.9 Compact dual-band resonator using anisotropic metamaterial - US
2008204327 (A1)
Summary
A dual-band resonator with compact size, such as a resonant type dual-band antenna, which uses an
anisotropic metamaterial is described. The artificial anisotropic medium is implemented by employing
a composite right/left-handed transmission line. The dispersion relation and the antenna physical size
only depend on the composition of the unit cell and the number of cells used. By engineering the
characteristics of the unit cells to be different in two orthogonal directions, the corresponding
propagation constants can be controlled, thus enabling dual-band antenna resonances. In addition,
the antenna dimensions can be markedly minimized by maximally reducing the unit cell size. A dual-
band antenna is also described which is designed for operation at frequencies for PCS/Bluetooth
applications, and which has a physical size of 1/18λ0 x 1/18λ0 x 1/19λ0, where λ0 is the free space
wavelength equal 2.37 GHz.
4.1.10 Metamaterial structures for light processing and methods of processing
light - WO 2008094543 (A1)
Summary
This patent describes a metamaterial structure for light processing including a light guide and a
composite resonant electromagnetic structure having a resonant frequency. The composite resonant
electromagnetic structure is arranged to interact with light propagating along the light guide to
upconvert a frequency of the light to the resonant frequency, which generates second and higher
harmonics of the light frequency. Methods of processing light are also presented.
4.1.11 Method and apparatus for reduced coupling and interference between
antennas
Summary
This patent describes antennas and scattering elements having a metamaterial cloak configured that
allows reducing effects on the operating parameters of a nearby antenna. For example, a cloak is
disposed around an antenna operating at a frequency range in which the cloak is also operative. The
antenna frequency can lie outside the frequency range of the cloak, whereas the frequency of a
second antenna lies within the frequency range of the cloak. In such a case, the first antenna will be
cloaked relative to the second antenna.
46
4.2. Environment
4.2.1 Molecular and photonic nanostructures, optical biomaterials,
photosensitizers, molecular contrast agents, and metamaterials - WO
2008130383 (A2)
Summary
This patent generally relates to new photo-physical characteristics associated with certain
macromolecules, heterogeneous phases with a pronounced index of refraction contrast, and biological
complex macromolecules. Given this, in one embodiment the present invention relates to new
processes, methods and applications, for enhancing signals and images. In another embodiment, the
present invention includes the design and development of scalable imaging systems and techniques,
optical instrumentation and lenses, systems engineering, photonics and optoelectronics, low-power
microelectronics, micronanotechnology, and sensing/biosensing applications for various applications
(e.g., life science applications).
4.3. Health & Well-Being
4.3.1 Photonic funnels and anisotropic waveguides for subdiffraction light
compression and pulse management at the nanoscale - US 2008219628
(A1)
Summary
The present invention provides an apparatus which allows propagation of electromagnetic radiation of
a selected vacuum wavelength beyond the diffraction limit. The apparatus comprises a waveguide
core and a cladding disposed about the core. The waveguide core may include a material with an
anisotropic dielectric permittivity, with the optical axis of the material primarily aligned with direction of
light propagation. In addition, the waveguide core may have a cross-sectional dimension smaller than
about half the selected wavelength at least at one portion of the waveguide core. The cross-sectional
dimension of the waveguide core may decrease along the length of the waveguide core creating a
taper to provide a photonic funnel. The waveguide core may include a homogeneous anisotropic
material, anisotropic metamaterial, or a photonic crystal.
4.4. Safety & Security
4.4.1 Efficient terahertz sources by optical rectification in photonic crystals and
metamaterials exploiting tailored transverse dispersion relations - US
2007297734 (A1)
Summary
47
A system and a method for generating terahertz radiation are provided in this patent. The
system includes a photonic crystal structure comprising at least one nonlinear material that
enables optical rectification. The photonic crystal structure is configured to have the suitable
transverse dispersion relations and enhanced density photonic states therefore allowing
terahertz radiation to be emitted efficiently when an optical or near infrared pulse travels
through the nonlinear part of the photonic crystal.
4.4.2 Active terahertz metamaterial devices - WO 2008121159 (A2)
Summary
Metamaterial structures, which provide for the modulation of terahertz frequency signals, are shown.
Each element within an array of metamaterial elements comprises multiple loops and at least one gap.
The metamaterial elements may include resonators with conductive loops and insulated gaps, or the
inverse in which insulated loops are present with conductive gaps, each providing useful transmissive
control properties. The metamaterial elements are fabricated on a semiconductor substrate configured
with means of enhancing or depleting electrons from near the gaps of the metamaterial elements. An
on-to-off transmissivity ratio of about one half is achieved by making use of this approach.
Embodiments are described in which the metamaterial elements incorporated within a quantum
cascade laser to provide surface emitting properties.
4.4.3 Three-dimensional left-handed metamaterial - WO 2008120556 (A1)
Summary
A three-dimensional left-handed metamaterial of totally new constitution functioning as a three-
dimensional electromagnetic wave propagation medium in which the equivalent permittivity and
permeability of the medium have negative values simultaneously is presented. The three dimensional
left-handed metamaterials of such a structure as cubic unit lattices are arranged repeatedly in three
orthogonal directions of a three-dimensional space which has first particulate bodies of conductor
arranged around each vertex of the unit lattice, second particulate bodies of conductor arranged
around the center of each face of the unit lattice, first coupling portions of conductor for coupling the
first particulate bodies and the central point of the unit lattice, and second coupling portions of
conductor for coupling the second particulate bodies and the central point of the unit lattice.
4.4.4 Security mark - WO 2008110775 (A1)
Summary
A security mark that includes a metamaterial designed such that the properties of this metamaterial
provides authentication of the security mark described. The metamaterial may have a negative
refractive index. Moreover, an article may be secured by applying the metamaterial to the article such
that the properties of the metamaterial authenticate the article. The metamaterial may be arranged to
form an image when illuminated by terahertz radiation.
48
4.4.5 System, method and apparatus for cloaking - US 2008165442 (A1)
Summary
An apparatus and method of cloaking are described. An object to be cloaked is disposed such that the
cloaking apparatus is between the object and an observer. The appearance of the object is altered
and, in the limit, the object cannot be observed in such a manner that the background appears
unobstructed. The cloak is formed of a metamaterial where the properties of the metamaterial are
varied as a function of distance from the cloak interfaces, and the permittivity is less than unity. The
metamaterial may be fabricated as a composite material having a dielectric component and inclusions
of particles of sub-wavelength size, so as to have a permeability substantially equal to unity.
4.4.6 Electromagnetic cloaking method - CA 2590307 (A1)
Summary
A method of constructing a concealing volume comprises constructing a plurality of concealing volume
elements around a concealable volume. Each concealing volume element has a material parameter
arranged to direct a propagating wav e around the concealable volume.
4.4.7 Active radar system
Summary
An example of radar system for a vehicle comprises a radar antenna, operable to produce a radar
beam, and a lens assembly including at least one active lens assembly, through which the radar beam
passes. The radar beam has a field of view that is adjustable using the active lens. In some examples,
the active lens comprises a metamaterial, the metamaterial having an adjustable property such as an
adjustable negative index, the field of view being adjustable using the adjustable property of the
metamaterial.
4.5. Others
4.5.1 Metamaterials and resonance materials based on composites of liquid
crystal colloids and nano particles - SI 22508 (A)
Summary
This invention describes metamaterials and/or resonance materials based on composites of liquid
crystal colloids and nanoparticles as well as the procedure of their manufacture. According to the
patent, the nanoparticles are segregated in the area of topological defects created by colloid parts
integrated in the liquid crystal layer. The nanoparticles are localised in the vicinity of topological
defects which are either localised or delocalised where the size of the nanoparticles is smaller from
the size of colloid particles preferably in the size of the topological defect.
49
4.5.2 Metamaterials and resonant materials based on liquid crystal dispersions
of colloidal particles and nanoparticles - EP 1975656 (A1)
Summary
This invention presents a class of metamaterials and/or resonant materials and the method of their
production, whereby nanoparticles are segregated in the regions of topological defects, which are
formed by inclusion of colloidal particles in a layer of a nematic liquid crystal. The nanoparticles are
localized in the vicinity of topological defects, which can themselves be localized or delocalized,
whereas the size of the nanoparticles is smaller than the size of the colloidal particles, preferably of
the size of the diameter of the defect.
4.5.3 Enhanced substrate using metamaterials - WO 2007069224 (A2)
Summary
In enhancing signal quality through packages, metamaterials may be used. Metamaterials are
designed to make the signal act in such a way as to make the shape of the signal behave as though
the permittivity and permeability are different than the real permittivity and permeability of the insulator
used. In an example embodiment, a substrate is configured as a metamaterial. This metamaterial
provides noise protection for a signal line having a pre-determined length disposed on the material
mentioned. The substrate comprises a dielectric material having a topside surface and an underside
surface. A conductive material is arranged into pre-determined shapes having a collective length.
Dielectric material envelops the conductive material and the conductive material is disposed at a first
predetermined distance from the topside surface and at a second predetermined distance from the
underside surface. The collective length of the conductive material is comparable to the pre-
determined length of the signal line.
4.5.4 Fabrication of semiconductor metamaterials - US 2008138571 (A1)
Summary
A method of fabricating a semiconductor metamaterial is provided, comprising a sample of engineered
microstructured material that is transparent to electromagnetic radiation and one or more elongate,
high aspect ratio voids, passing through the voids a high pressure fluid comprising a semiconductor
material carried in a carrier fluid, and causing the semiconductor material to deposit onto the surface
of one or more voids of the engineered microstructured material to form the metamaterial. Many
microstructured materials and semiconductor materials can be used, together with various techniques
for controlling the location, spatial extent, and thickness of the deposition of the semiconductor within
the microstructured material, so that a wide range of different metamaterials can be produced.
50
4.5.5 Variable metamaterial apparatus - WO 2007098061 (A2)
Summary
Artificial materials, including metamaterials, exhibit adjustable properties. In some approaches the
properties are adjustable according to active feedback of interaction with electromagnetic waves.
5. Barriers
Several barriers related to technological and fabrication aspects have been identified by analysis of
the results and expert reviews. In this section, a summary of barriers regarding metamaterials use for
applications is given.
As seen on the different graphs presenting the publication related to metamaterials over the last years,
it appears that this field is relatively recent and therefore still at the level of basic research. Several
scientific and technological challenges still interfere with a possible wide commercial application and
usage of these materials. Mainly, losses of intensity due to absorption in the used metals of the metal
nanostructures are a critical issue, especially for the use of metamaterials as superlenses. Moreover,
fabrication of 2-dimensional and, even more, of 3 dimensional metamaterial nanostructures is very
challenging. The vision of creating cloaking devices for making objects invisible will only be accessible
when 3D metamaterial nanostructures will be fabricated with high homogeneity and reproducibility as
well as very low surface roughness.
Many experts have mentioned that it is necessary that metamaterials enter the market soon to initiate
a strong impulse on further development of this material type. For application of chiral metamaterials
as e.g. optical rotators and optical isolators, it is often mentioned that size of the devices is an issue.
The devices have to be reduced in size for getting commercially applicable. However, the field of
metamaterials shows to be promising while some companies such as Rayspan appear on the market
and show a rapid level of development.
51
6. Trends and future applications
The most significant advances in the use of metamaterials are currently being made in the microwave
part of the spectrum, due to the easiness in fabricating the devices based on metamaterials at these
wavelengths. This does not mean that devices working at higher frequencies cannot be made, though
the feasibility of the designs decreases as the work frequency increases. As previously seen, interest
in metamaterials has grown exponentially since the beginning of the 2000s. The potential of these
structures in various applications in the information and communication technologies sector is
considerable. This is the consequence of the outstanding performance of metamaterials in controlling
both the propagating and the evanescent part of the spectrum of the electromagnetic field. Such a
salient feature cannot be achieved with standard materials. Microelectronics, wireless comunication
systems, avionics, and many more industries may benefit from the following active sub-areas in
metamaterials, mainly at GHz frequencies.
This section aims to give some of the directions research on metamaterials may follow in the next few
years. It will be note that, although not mentioned in this part since it was covered earlier in this report,
cloaking as a metamaterial application remains a major centre of interest, if not the main one. This is
especially due to the spectacular character that may represent the possibility of hiding objects not only
in science-fiction movies but also in a scientific way.
6.1. Waveguide miniaturization
Waveguiding structures are often required in most of the applications of the microwave range
(between 0.3 and 300 GHz as a broad definition). Though the established methods and techniques to
fabricate such structures are highly-developed, issues regarding cost effective solutions and losses
still remain important [1]. Regarding these problems, metamaterials and photonic bandgap (PBG)
based waveguides structures have been identified as having a potential impact in sectors like avionics
and satellite communications [2,3], where beam-forming and losses in imprinted circuits are
challenging. However, PBG waveguides involve large-area designs, an adverse attribute for these
kinds of applications, because miniaturization is often a key in the fabrication of more competitive
solutions for imprinted circuits and waveguides. New alternatives consisting of metallodielectric [3-5]
periodic and even fractal structures have been considered. Moreover, left-handed materials are
believed to have the capacity to offer innovative solutions to waveguide problems design in terms of
size reduction and cost [6,7].
[1] FP6 Metamorphose NOE project: http://www.metamorphose-eu.org
[2] B. Temelkuran, and E. Ozbay, "Experimental demonstration of photonic crystal based
waveguides," Appl. Phys. Lett 74 (4), 486 (1999)
[3] P. de Maagt, "EBG components and applications at microwave and (sub)millimeter waves,"
European Microwave Week Workshop EuMC05, Amsterdam, 11-15 Oct 2004.
52
[4] P. Haring Bolívar, M. Brucherseifer, J. Gómez Rivas, R. Gonzalo, I. Ederra, A. Reynolds, M.
Holker, and P. de Maagt, "Measurement of the dielectric constant and loss tangent of high
dielectric constant materials at terahertz frequencies," IEEE Trans. Microw. Theory Tech. 51, 1062
(2003)
[5] J. C. Vardaxoglou, A. P. Feresidis and G. Goussetis, "Metallodielectric EBG surfaces:
miniaturization, tuneability and antenna applications," Proceedings of the Workshop on
Metamaterials for Microwave and Optical Technologies, San Sebastian, Spain, 18-20 July 2005
[6] Y. Horii, C. Caloz, and T. Itoh, "Super-compact multilayered left-handed transmission line and
diplexer application," IEEE Trans. Microw. Theory Tech. 53, 1527 (2005)
[7] A. J. Viitanen, and S. A. Tretyakov, "Metawaveguides formed by arrays of small resonant particles
over a ground plane," J. Opt. A: Pure Appl. Opt. 7, S133 (2005)
6.2. Dispersive waveguides
As a consequence of the uncommon characteristics of metamaterials, waveguides and transmission
lines made using such materials could have a better performance when controlling dispersive effects
than standard waveguides based on right-handed material [1]. Backward lines, subwavelength
transmission plasmonic waveguides, and even waveguides on a uniaxial, dispersive metamaterials
are subjects of investigation concerning dispersion issues. The most valuable advantaged of such
structures is the dispersion control, thus finding a direct application in communication systems [2,3].
Broadband matching can be achieved if a combination of backward and forward lines is properly
designed [4]. A straightforward conclusion stems from such a device: no matching networks are
required in order to minimize the losses due to reflections in the structure [5].
[1] FP6 Metamorphose NOE project: http://www.metamorphose-eu.org
[2] M. Bayindir, B. Temelkuran, E. Ozbay, "Propagation of photons by hopping: A waveguiding
mechanism through localized coupled cavities in three-dimensional photonic crystals," Phys Rev.
B 61 (18), 11855 (2000)
[3] A. K. Iyer and G. Eleftheriades, "Negative-refractive-index transmission line metamaterials and
applications," Proceedings of the Workshop on Metamaterials for Microwave and Optical
Technologies, San Sebastian, Spain, 18-20 July 2005
[4] A. Lai, C. Caloz, and T. Itoh, "Composite left-/right-handed transmission line metamaterials," IEEE
magazine, Sept 2004
[5] S. Zubko, D. Kholodnyak, I. Kolmakova, I. Kolmakov, A. Lapshine, E. Serebryakova, O. Vendrik
and I. Vendik, "Broad band microwave phase shifters based on a combination of left and right-
handed transmission lines," Proceedings of the Workshop on Metamaterials for Microwave and
Optical Technologies, San Sebastian, Spain, 18-20 July 2005
53
6.3. Antennas / antenna arrays
As previously discussed in section 3.2, emission and reception performance of antennas have shown
to be improving when metamaterials are employed as sub/superstrates of individual antennas and
antennas arrays. These observations therefore open the way to an optimization of their most
significant merit figures [1]. Higher directivity, smaller cross-talking between each element of the array
and reduction of lateral lobes are realized owing to these structures in the microwave and millimetre
wave range. Focusing on some multi-antenna arrangements [2], directivity values around 10dB have
been reached by means of a metamaterial superstrate. At the same time, the cross-talking between
elements of the array can be substancially decreased. Some remarkable applications have their roots
on the properties that metamaterials exhibit. A smart design of novel leaky wave antennas can be
done throughout their use, making possible the fabrication of full-space scanning antennas [3]. Finally,
single excitation of dual-band antennas [4] and small antennas [5,6] are subjects of intense
investigation.
[1] FP6 Metamorphose NOE project: http://www.metamorphose-eu.org
[2] E. Sáenz Sainz, "Design of multifrequency anetenna array with the use of left-handed
superstrates," Proceedings of the Workshop on Metamaterials for Microwave and Optical
Technologies, San Sebastian, Spain, 18-20 July 2005
[3] G. Donzelli, F. Capolino, S. Boscolo, M. Midrio, "Absence of scan blindness in phased arrays with
grounded dielectric EBG substrate," Proceedings of the Workshop on Metamaterials for
Microwave and Optical Technologies, San Sebastian, Spain, 18-20 July 2005
[4] C. Caloz, and T. Itoh, "Array Factor Approach of Leaky-Wave Antennas and Application to 1-D/2-
D Composite Right/Left-Handed (CRLH) Structures," IEEE Microw. Wireless Compon. Lett. 14,
274 (2004)
[5] C. Caloz, "Novel metamaterial antennas and reflectors," Proceedings of the Workshop on
Metamaterials for Microwave and Optical Technologies, San Sebastian, Spain, 18-20 July 2005
[6] R.W. Ziolkowski and A.D. Kipple, "Reciprocity between the effects of resonant scattering and
enhanced radiated power by electrically small antennas in the presence of nested metamaterial
shells," Phys. Rev. E 72, 036602 (2005)
6.4. High impedance surfaces and artificial magnetic conductors
Different metamaterials working in the gigahertz range, such as high impedance surfaces and artificial
magnetic conductors attract much interest for research because of their fast time-to-market
implementation [1]. They could serve as a solution to miniaturize and reduce the cost in the
information and communication systems sector. In fact, at this stage components based on these
structures already exist and are available on the market [2-5]. The main efforts are devoted to
substrates, superstrates and absorbers for a heterogeneous set of antennas [6-8].
54
[1] P6 Metamorphose NOE project: http://www.metamorphose-eu.org
[2] D. Sievenpiper, "High-impedance electromagnetic surfaces with a forbidden frequency band,"
IEEE Trans. Microwave Theory Tech. 47, 2059 (1999)
[3] J. McVay, N. Engheta, and A. Hoorfar, "High-impedance metamaterial surfaces using Hilbert-
curve inclusions," IEEE Microwave and Wireless Components Lett. 14, 130 (2004)
[4] A. Ourir, A. de Lustrac, and J.-M. Lourtioz, "All-metamaterial based subwavelength cavities for
ultrathin directive antennas," Appl. Phys. Lett. 88, 084103 (2006)
[5] F. Bilotti, M. Manzini, A. Alù, and L. Vegni, "Polygonal patch antennas with reactive impedance
surfaces," J. Elect. Waves and Applications 20, 169 (2006)
[6] A. Alù, F. Bilotti, N. Engheta, and L. Vegni, "Design of conformal omnidirectional metamaterial
antennas," Proc. 18th Int. Conf. on Applied Electromagnetics and Communications (2005)
[7] M.F. Wu, F.Y. Meng, Q. Wu, J. Wu, J.C. Lee, "An approach for small omnidirectional microstrip
antennas based on the backward waves of double negative metamaterials," Appl. Phys. A 87, 193
(2007)
[8] S.A. Tretyakov, S.I. Maslovski, "Thin absorbing structure for all incidence angles based on the use
of a high-impedance surface," Microwave and Optical Technology Letters 38, 175 (2003)
6.5. Tuneable materials
As mentioned above, metamaterials can be considered artificial, periodic structures where “basic
units” inclusions, properly patterned in a substrate, depict different properties than usual materials in
regard to the interaction of light with them. Those basic units can be made of materials whose physical
properties can be modulated in some way or other [1]. Therefore far more flexible sensors and devices
could be fabricated based on the tuneability of the striking properties of the metamaterials. This would
be beneficial for low-cost steering antennas, ferrites, composite materials for microwave applications.
Generally speaking, imaging systems for healthcare applications, security and environmental control,
and terrestrial/space observation are fields of interest. Although these sub-fields of research have
obvious connections with small and medium enterprises and the market in general, the extension of
the ideas and patents developed within the field will probably take time to enter in the market.
[1] P6 Metamorphose NOE project: http://www.metamorphose-eu.org
6.6. Summary
The overview presented in this patent-section can be completed through the data displayed in Figure
5, where a patent search on “Metamaterials” from 2004 to 2008 is shown. Most of the patents are
devoted to application in the industrial sector of information and communications. However, as it will
be seen further on, the metamaterial field of research is also expected to extend towards other sectors
in the short run.
55
Figure 5 Number of patents on Metamaterials during the period 2004-2008 (source:
esp@cenet patents database)
Taking into consideration the information previously presented, the most remarkable features
regarding trends and future applications of metamaterials at optical frequencies can be observed.
Figure 6 present the future trends in the field of metamaterials at optical frequencies over the next few
years.
56
Figure 6 Trends in metamaterial research and development at optical frequencies for the next few
years (source: Metamorphose FP6 NOE project)
Combining the content of Figure 6 with information presented in this report, it can be said that the
overwhelming majority of the applications in the four sectors are developed at frequencies other than
the optical part of the spectrum. These applications related to metamaterials structures can be listed
depending on their functionality as follows:
1. Collimation: MRI imaging for health applications (Health & Well-being)
2. Superlensing: Imaging, detection and focusing of radiation (Safety & Security, Health &
Well-being)
3. Sensing: Biosensor based on metamaterials (Health & Well-being, Safety & Security)
4. Multifunctionnal reconfigurable systems: Frequency selectives surfaces, small antennas,
tunable filters, delay lines, integration of MEMs switches, cloaking, wireless
communications.
At optical frequencies the following applications can be identified: nanoantennas, plasmonic
nanocircuits, cloaking (ICT, Safety & Security).
57
These are the most relevant trends and future applications of metamaterials being investigated. Most
of them are devoted to the microwave and millimeter wave regime because of the problems involved
in the fabrication of devices at the nanoscale (feasibility and reproducibility). However, there is a
clearly growing interest in extending designs and concepts from the microwave regime to the optical
one.
7. Information sheets on relevant photonic materials
Based on the results obtained in parts 2, 3 and 4, about 20 to 30 relevant photonic materials will be
identified in each category, which have a high potential for future industrial applications. In this part it
is crucial to explain the advantages of these photonic materials and why these photonic materials
have a high potential for future applications or what is the scientific / technological breakthrough
achieved. E.g. it is necessary to explain which property of the material has been improved and also it
is important to mention the problems, which are still to be overcome.
For each material identified with a high potential, an information sheet/table has to be filled in (cf.
template which is developed by the roadmap experts), with :
its relevant properties (optical, electrical, …) which are of interest / have been improved,
industrial applications (actual and future),
production process,
phase of development.
58
8. Imprint
This report has the objective to give an overview on the recent scientific research and development
undertaken in the field of optical fibres and has not the goal to be exhaustive.
This R&D report analysis was compiled within the European project “Development of Advanced
Technology Roadmaps in Photonics and Industrial Adaptation to Small and Medium sized Enterprises”
(“PhotonicRoadSME”). The project is funded by the European Commission under the “Seventh
Framework” Programme (Project Number 224572).
Authors:
Dr. José-Maria Rico García (Optics Department, Universidad Complutense de Madrid)
Mr. Mario González Montes (Optics Department, Universidad Complutense de Madrid)
Dr. Goran Markovic (Steinbeis-Europa-Zentrum)
Dr. Jonathan Loeffler (Steinbeis-Europa-Zentrum)
Contact of project co-ordinator:
Dr. Jonathan Loeffler
e-mail: [email protected]
Steinbeis-Europa-Zentrum
Erbprinzenstraße 4-12, 76133 Karlsruhe
Germany
The authors are responsible for the content. All rights reserved except those agreed by contract.
No part of this publication may be translated or reproduced in any form or bay any means without prior
permission of the authors.
Version October 2009