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1

Photonic CrystalsPhotonic Crystals

Photonics Research Laboratory

Department of Electrical and Computer Engineering

Old Dominion University, Norfolk, VA 23529

http://www.lions.odu.edu/~salbin/Photonics/

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Research TeamResearch Team

Dr. Sacharia AlbinAdvisor

Dr. Shangping GuoPost Doc Fellow

Feng WuPh.D. Candidate

Khalid IkramMaster’s Student

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Periodic structures in 1D, 2D and 3D Period comparable to wavelength (sub-microns) Possess photonics band gaps (PBGs) which prohibit any light modes Obey Maxwell’s equations, predicting fields accurately Similar but fundamentally different from semiconductors

1887 1987

IntroductionIntroduction2-D

periodic intwo directions

3-D

periodic inthree directions

1-D

periodic inone direction

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No electrons

No photons

No EMAG Radiation Inside No EMAG Radiation Inside PBGPBG

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Woodpile PBG using Silicon Woodpile PBG using Silicon Micro-machiningMicro-machining

From Sandia National LaboratoryFrom Sandia National Laboratory

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Photonic MicropolisPhotonic Micropolis

Research at MIT

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Planar photonic devices based on 2D photonic crystals Basic geometries: square, triangular, honeycomb, kagome

X

1st BZ

K M

Research at ODU Photonics LabResearch at ODU Photonics Lab

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Optical insulator Perfect dielectric mirror Optical filter Polarizer Super-lensing Negative refraction

Examples of Photonic Examples of Photonic Devices/ApplicationsDevices/Applications

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Point defects and line defects High Q filter Zero-threshold cavity Resonance center for controlled energy transfer Linear waveguiding & bending Ideal integrated devices

Defects in PBGDefects in PBG

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PBG provides: High Q cavity + ASE suppression, leading to micro sized, zero-threshold laser.

From UCLA

PBG Defect LaserPBG Defect Laser

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Resonant cavity: high Q filter ~10,000, resonant frequency, Q and energy pattern can be designed.

S. Guo, S. Albin, “Numerical techniques for excitation and analysis of defect modes in photonic crystals”, Opt. Express 11, 1080-1089 (2003)

Example of High Q filterExample of High Q filter

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Possible high Q filters in a 2D square lattice, useful for many devices: add/drop, waveguiding cross, splitter, filters, etc.

S. Guo, S. Albin, “Numerical techniques for excitation and analysis of defect modes in photonic crystals”, Opt. Express 11, 1080-1089 (2003)

Example of High Q filterExample of High Q filter

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Field Profile – Single DefectField Profile – Single Defect

S. Guo, S. Albin, “Numerical techniques for excitation and analysis of defect modes in photonic crystals”, Opt. Express 11, 1080-1089 (2003)

14Linear waveguiding in arbitrary medium

S. Guo, PhD Dissertation, ODU, 2003

Example of Linear WaveguideExample of Linear Waveguide

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Peaks in transmission spectrum, due to the cavity resonant effect, or DBR effect (contributes to special dispersion)

Phase relationS. Guo, PhD Dissertation, ODU, 2003

Linear Waveguide : Pulse Linear Waveguide : Pulse PropagationPropagation

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Coupled Cavity WaveguideCoupled Cavity Waveguide

S. Guo, PhD Dissertation, ODU, 2003

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Coupled Cavity WaveguideCoupled Cavity Waveguide

5 cavities, 5 peaks in the transmission Large propagation delay in the cavity (delay line) A setup time required Distortion of ultra-narrow pulses

S. Guo, PhD Dissertation, ODU, 2003

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100% Transmission at Sharp 100% Transmission at Sharp BendsBends

S. Guo, PhD Dissertation, ODU, 2003

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Pulse Propagation Through Pulse Propagation Through Sharp BendsSharp Bends

Whole band can pass the bend with transmission over 80%

Peak transmission occurs at some frequencies due to waveguiding and resonant tunneling at the bend

S. Guo, PhD Dissertation, ODU, 2003

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Add/drop channels using CCWsAdd/drop channels using CCWs

XX

S. Guo, PhD Dissertation, ODU, 2003

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CCW for add/drop ChannelsCCW for add/drop Channels

S. Guo, PhD Dissertation, ODU, 2003

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Photonic Crystal FiberPhotonic Crystal Fiber

Holey fiber with a micro-structured cladding

Photonic band gap fiber: guiding light in air

Bragg fiber using perfect cylindrical dielectric mirrors (the Omniguide fiber)

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Microstructured holey fiber or PCFs, Russel et al, Science, 2003 (Univ. Bath)

Holey FibersHoley Fibers

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Spatial DispersionSpatial Dispersion

S. Guo, PhD Dissertation, ODU, 2003

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Index-guiding Triangular PCFIndex-guiding Triangular PCFEndless Single ModeEndless Single Mode

Single mode from UV to infrared Short wavelength gets a better confinement

S. Guo, PhD Dissertation, ODU, 2003

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Air-guiding PCFsAir-guiding PCFs

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Bragg Fiber with Omni-Bragg Fiber with Omni-ReflectorReflector

Omnidirectional Mirrors

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AdvantagesAdvantages

Light guiding (at any wavelength) in air, e.g. the CO2 laser transport for medical applications

No need for high purity materials Reduced nonlinear effect, zero polarization

mode dispersion, large power transfer Asymptotic single mode propagation

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Modeling and Simulation Modeling and Simulation MethodsMethods

Photonics lab has developed many methods for the research on photonic crystals

Plane wave method: to calculate the band gap structure of any photonic crystal

Time-domain: for band gap calculation FDTD: to simulate the field dynamics in

arbitrary dielectric materials. Fiber, PCF, Bragg fiber analysis tools

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The PWM and FDTD methods Solved most problems in PBG field Our free software used by hundreds of users world

wide Dedicated discussion group Citation by peer groups

Fiber Analysis Modified plane wave methods Galerkin method: Laguerre-Gauss, Hermite-Gauss Compact-2D FDTD for waveguides FDFD for arbitrary fibers

Modeling and Simulation Modeling and Simulation MethodsMethods

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Related PublicationsRelated Publications1. F. Wu, S. Guo, K. Ikram, S. Albin, H. Tai, B. Rogowski, “Numerical analysis of

Bragg fibers using a compact 1D finite-difference frequency-domain method,” Opt. Comm. 249, 165-174 (2005).

2. S. Guo, F. Wu, S. Albin, H. Tai, B. Rogowski, “Loss and dispersion analysis of microstructured fibers by finite-difference method,” Opt. Express 12, 3341-3352 (2004).

3. S. Guo, F. Wu, S. Albin, B. Rogowski, “Photonic band gap analysis using finite-difference frequency-domain method”, Opt. Express 12, 1741-1746 (2004).

4. S. Guo, F. Wu, K. Ikram, S. Albin, “Analysis of circular fiber with arbitrary index profiles by Galerkin method”, Optics Letters 29,32-34 (2004).

5. S. Guo, S. Albin, B. Rogowski, "Comparative analysis of Bragg fibers," Opt. Express 12, 198-207 (2004).

6. S. Guo, S. Albin, “Numerical techniques for excitation and analysis of defect modes in photonic crystals”, Opt. Express 11, 1080-1089 (2003).

7. S. Guo, S. Albin, Simple plane wave implementation for photonic crystal calculations, Opt. Express 11, 167 (2003).

8. S. Guo and S. Albin, “Transmission property and evanescent wave absorption of cladded multimode fiber tapers”, Opt. Express 11, 215-223 (2003).

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AcknowledgmentsAcknowledgments

This research is supported by NASA Langley Research Center through

NASA-University Photonics Education and Research Consortium (NUPERC)

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