Single-photon sources (2005)

Abstract The article surveys the state of the art in the design, development and application of devices for deterministically generating single photons on demand. Both the defined function and requisite form of such 'single-photon' sources are explained in detail. Their attributes and characteristics, in particular the photon-counting statistics of the light that they generate, are presented in conjunction with the experimental apparatus (most notably the Hanbury-Brown and Twiss interferometer) for measuring them. Promising applications of single-photon sources within quantum key distribution, quantum information processing, as well as metrology and fundamental tests of quantum mechanics, are described. The utility and relative advantages of single-photon sources vis-á-vis more conventional sources of light are explained in terms of application-specific requirements and the respective abilities of different sources to fulfil them. The article collects, classifies and sorts the most significant work towards realizing practical single-photon sources to date. Though emanating from a diverse set of technological disciplines, with different research and application objectives in mind, the relative advantages and drawbacks of each approach are assessed, to give the reader a broad yet coherent and critical review of a rapidly developing research front. Acknowledgments The writing of this review has been possible with support from the UK Department of Trade and Industry's Quantum Metrology Programmme (2001 – 2004) and the UK National Physical Laboratory's Strategic Research Programme. The authors wish to thank the following for providing their original figures from research papers: P. Grangier, G. Rempe, P. Michler, A. Imamoğlu, C. Santori, Y. Yamamoto, A.J. Shields and M. Pepper. The authors also acknowledge permission granted by the American Physical Society, the Optical Society of America, the American Association for the Advancement of Science, and the Nature Publishing Group to reproduce original figures from research papers. MO would like to thank K. Gottfried and V. Ambegaokar for tolerating and influencing his early thoughts on quantum mechanics. Finally, the authors thank J. Rarity, P. Tapster, H. Weinfurter, R. Mirin, A. Collins and the editor for various forms of help and advice. Notes Mark Oxborrow earnt a PhD on the application of random-tiling models to the atomic structure of quasicrystals from Cornell University, where he worked in passing on the representation and dynamics of irreversible processes in quantum mechanics. During postdoctoral appointments at both the Niels Bohr Institute in Copenhagen and the University of Oxford, he investigated acoustic analogues of quantum wave-chaos. He currently works at the UK's National Physical Laboratory, where his duties include the design and construction of ultrastable microwave and optical oscillators, the development of single-photon sources and the applications of carbon nanotubes to metrology. Alastair Sinclair is also a Principal Research Scientist at the National Physical Laboratory. He studied at the University of Strathclyde, where he researched laser cooling of neutral atoms. As a postdoctoral research fellow at Stanford University, he worked towards observing quantum statistical effects in ultracold samples of lithium atoms. His current research activities include laser cooling of trapped ions for quantum information, the development of single-photon sources, and also quantum measurement. Since the writing of this article, a directly relevant collection of research papers was published in a Focus Issue of the New Journal of Physics [184], entitled 'Single Photons on Demand'. Additional informationNotes on contributorsMark Oxborrow Mark Oxborrow earnt a PhD on the application of random-tiling models to the atomic structure of quasicrystals from Cornell University, where he worked in passing on the representation and dynamics of irreversible processes in quantum mechanics. During postdoctoral appointments at both the Niels Bohr Institute in Copenhagen and the University of Oxford, he investigated acoustic analogues of quantum wave-chaos. He currently works at the UK's National Physical Laboratory, where his duties include the design and construction of ultrastable microwave and optical oscillators, the development of single-photon sources and the applications of carbon nanotubes to metrology. Alastair Sinclair is also a Principal Research Scientist at the National Physical Laboratory. He studied at the University of Strathclyde, where he researched laser cooling of neutral atoms. As a postdoctoral research fellow at Stanford University, he worked towards observing quantum statistical effects in ultracold samples of lithium atoms. His current research activities include laser cooling of trapped ions for quantum information, the development of single-photon sources, and also quantum measurement.