Quantum photonics: nitrogen-vacancy centers in diamond

by Tejasvi Parupudi, Amr Emadeldin, Rajtarun Madangopal, and Mikhail Shalaginov

Stuck in the Internet highway "traffic" jam

Phil Kerpen"Information super traffic jams", Forbes 2007

Promising ways of developing IT

• Optical computing

• Quantum computing

• Quantum cryptography

• Spintronics

• DNA computing

• Artificial intelligence

Opportunities

Quantum entanglement and teleportation of well secured information,much faster mechanisms of processing information

Shor’s algorithm

Macroscopic "single-photon" sources

Lounis and Orrit, Rep. Prog. Phys. 68 (2005) 1129–1179

Trapped ions:Cs, Rb

Color centers in diamond Quantum dots

Microscopic single-photon sources

Nitrogen-vacancy color center in diamond as one of the best candidates to be used in future quantum technologies as a single-

photon source

Nitrogen Vacancy Center

Aharonovich et al., Nature Photonics, 2011

NANODIAMONDS

•Detonation process

•Microwave-assisted CVD

•Crushing of synthetic/natural diamonds

DIAMOND WAFERS

HPHT/ High-plasma density CVD -single crystal diamond wafers fabrication

Aharonovich et al., Nature Photonics, 2011

C. Bradac, et al., Nature Nanotechnology, 5, 345-349 (2010)

•Nitrogen – most common impurity;•Irradiation with electron/He2+ –creation of vacancies;•Annealing – diffusion of vacancies and subsequent formation of NVs

Robledo et al., PRL 105, 177403, 2010

Electronic level structure of NV center

Pham et al. New Journal of Physics (2011) vol. 13 pp. 045021

Spectrum of NV center

S. Schietinger, Nano Lett, 8,11, 2008

2nd order correlation function g(2)(τ)

http://spie.org/x40194.xml?ArticleID=x40194

Properties of NV Centers

Stable against photobleachingKurtsiefer et al., PRL, 85, 2, 2000

Long spin coherence times > 1.8 ms Stanwix et al., arXiv, Cond. Matter, 2011

Room temperature single spin read outStanwix et al., arXiv, Cond. Matter, 2011

Photoluminiscence at room temperatureKennedy et al., APL, 83, 20, 2003

Promising applications of NV-centers in quantum

computing

Quantum computation

• ıc›=a ıo› + b ı1›

• Coherence

• Entanglement

• Secure communications

• Shor’s algorithm

• Grover’s algorithm (entanglement to process multi-states in parallel)

Using nanodiamond NV centers for quantum processing

Single photon sources could be coupled to cavities (CQED)

Two approaches:• NV centers contain qubits coupled and entangled with

photons

• Photons are qubits entangled by non-linearities in NV centers (like EIT)

Repeat until success

Lim et al, “Repeat until success quantum computing”, U Cmabridge,2008

Bell measurement, interferometry ,

Grentree et al , “Diamond integrated quantum photonics”

Brokered graph-state quantum computation

Weak non-linearities

• Single-photon generation

• Entanglement parity operation

• Non-demolition measurement

Munro et al, “weak non-linearities: A new route to optical quantum computation ” 2005

Electromagnetic Induced Transparency

• Equivalent to Kerr effect, EIT is the source of non-linearity

• Applicable to diamond case

Beasoleile et al, “Application EIT to Quantum Information Processing ”, 2004

Coupling photons to surrounding

• Cavity QED

• Photonic module

Diamond for quantum computing

Other promising applications of NV-centers in diamond

Ampem-Lassen et al. Opt Express (2009) vol. 17 (14) pp. 11287-93

Fluorescence emission from NV center

NanoDiamond vs. Other ‘Fluorophores’

Say et al. Biophysical Reviews (Oct 2011)

Fluorescent NanoDiamonds for Imaging

Chang et al, Nature Nanotechnology (2008) vol. 3 (5) pp. 284-288

Imaging of both fast (ms) and slow (h) events in cells, tissues & even small animals.

3D tracking of a single 35-nm FND in a live HeLa cell 3D TPE image of cell and internalized FNDs

OPE and TPE confocal fluorescence images of same cell Epifluorescence & 3D reconstruction

Hell et al., Current opinion in Neurobiology (2004) vol. 14 (5) pp. 599-609

Stimulated Emission Depletion Microscopy

Stimulated Emission Depletion Microscopy

Hein et al. Proceedings of the National Academy of Sciences (2008) vol. 105 (38) pp. 14271

Aharonovich et al., Nature Photonics (2011) vol. 5 pp. 397-405

NV Color Centers & STED• Conventional fluorescent markers

have limited photostability & get photobleached.

• QDs are photostable but not compatible with STED

• NV centers are photostable – limited photobleaching at high excitation intensities.

Pham et al. New Journal of Physics (2011) vol. 13 pp. 045021

NV Center’s electronic structure allows:• Optical initialization and detection of the spin state• Long room temperature spin coherence times

Nanoscale Magnetic Sensing & Magnetic Field Imaging

Pham et al. , New Journal of Physics (2011) vol. 13 pp. 045021

Magnetic Field Imaging

ConclusionsNitrogen-vacancy (NV) center – promising microscopic single-photon source.

Important properties:

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Other promising applications:

•photostable, •operates at room temperature, •broadband emission spectrum, •long spin coherence time,•non-toxic.

•biolabeling,•fluorescent imaging (with STED), •magnetic sensing and magnetic field imaging.

Bonus Movie

Appendix

Quantum photonics: nitrogen-vacancy centers in diamond

by Tejasvi Parupudi, Amr Emadeldin, Rajtarun Madangopal, and Mikhail

Shalaginov