Diamond’s light touch

Australian Institute of Physics Congress

US researchers reported on their ability to create diamond nanowires  which could one day be used to power quantum computers with many times the processing power of today’s supercomputers.

These diamond nanowires can provide the steady stream of photons needed for light-based quantum computers, says Tom Babinec from the Marko Lončar’s Laboratory for Nanoscale Optics at Harvard University.

Further information:

Diamond Nanophotonics and Quantum Optics

Marko Lončar, Tom Babinec, Jennifer Choy, Birgit Hausmann, Irfan Bulu, Murray McCutcheon School of Engineering and Applied Science, Harvard University, Cambridge, MA 02138, USA loncar@seas.harvard.edu, http://nano-optics.seas.harvard.edu

Abstract summary:

We describe a high-flux, room temperature, source of single photons based on an individual Nitrogen-Vacancy (NV) center embedded in a top-down nanofabricated, single crystal diamond nanowires.


Individual color centers in diamond have recently emerged as a promising solid-state platform for quantum communication and quantum information processing systems, as well as sensitive nanoscale magnetometry with optical read-out. Performance of these systems can be significantly improved by engineering optical properties of color centers using nanophotonic approaches. In this work we describe a highfl ux, room temperature, source of single photons based on an individual Nitrogen-Vacancy (NV) center embedded in a topdown nanofabricated, single crystal diamond nanowires [1]. Using the nanowire geometry, an order of magnitude brighter single photon source is realized, with an order of magnitude lower pump power, compared to an NV center in a bulk diamond [2]. We also describe fabrication process that combines ion implantation of nitrogen with nanowires fabricated in high-purity diamond crystals [3]. This approach significantly improves single-photon properties of our devices. By embedding nanowires in metals, it is possible to further increase photon production rate (via Purcell effect), as well as improve collection efficiency of emitted photons [4]. Finally, we will describe photonic crystal nanobeam cavity [5] that, when realized in diamond [6] or materials transparent at visible wavelengths [7], can enable strong coupling between photons and NV centers.


1. B.M. Hausmann, M. Khan, T.M. Babinec, Y. Zhang, K. Martinick, M.W. McCutcheon, P.R. Hemmer, M. Lončar, “Fabrication of diamond nanowires for quantum information processing applications,” Diamond and Related Materials, 19, 621 (2010)

2. T.M. Babinec, B.M. Hausmann, M. Khan, Y. Zhang, J. Maze, P.R. Hemmer, M. Lončar, “A bright single photon source based on a diamond nanowire,” Nature Nanotechnology, 5, 195 (2010)

3. B.J.M. Hausmann*, T.M. Babinec*, J.T. Choy*, J.S. Hodges, S. Hong, I. Bulu, A. Yacoby, M.D. Lukin, and M. Lončar, “Single Color Centers Implanted in Diamond Nanostructures”, arXiv:1009.4224 (2010)

4. B. Hausmann, I. Bulu, T. M. Babinec, M. Khan, P. Hemmer, M. Loncar, “Plasmonic Nanocavities for Quantum Information Processing with Diamond Color Centers”, CLEO 2010

5. P. B. Deotare, M. W. McCutcheon, I. W. Frank, M. Khan, and M. Lončar, “High Quality factor photonic crystal nanobeam cavities,” Applied Physics Letters, 94, 121106 (2009)

6. T.M. Babinec, J.T. Choy, K.J.M. Smith, M. Khan, and M. Lončar, “Design and Focused Ion Beam Fabrication of Single Crystal Diamond Nanobeam Cavities,” arXiv:1008.1431 (2010)

7. M. W. McCutcheon, and M. Lončar, “Design of a silicon nitride photonic crystal nanocavity with a Quality factor of one million for coupling to a diamond nanocrystal”, Optics Express, 16, 19136 (2008).


Tom Babinec, babinec@fas.harvard.edu