Fiber-Coupled Cavity-QED Source of Identical Single Photons

An ordered stream of single photons is fundamentally different from conventional light, which features bunches of random numbers of photons. Single-photon sources are essential for emerging technologies in $e.g.$ quantum cryptography and computing, but widespread use of bright quantum-dot sources has been thwarted by the need for complex optical setups. Thus the authors present a $f\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}b\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}r-i\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}g\phantom{\rule{0}{0ex}}r\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}d$ source of high-quality single photons. This marriage with conventional optical-fiber technology will not only promote broad use in quantum photonics, but also may enable fundamental studies in fields from microscopy to quantum metrology, by significantly simplifying experiments.