用于量子光通信的单光子晶体管

Demonstration of spatial-light-modulation-based four-wave mixing in cold atoms

Long-distance quantum optical communications usually require efficient wave-mixing processes to convert the wavelengths of single photons. Many quantum applications based on electromagnetically induced transparency (EIT) have been proposed and demonstrated at the single-photon level, such as quantum memories, all-optical transistors, and cross-phase modulations. However, EIT-based four-wave mixing (FWM) in a resonant double-$Λ$ configuration has a maximum conversion efficiency (CE) of 25% because of absorptive loss due to spontaneous emission. An improved scheme using spatially modulated inten…

Nanophotonic quantum phase switch with a single atom

In analogy to transistors in classical electronic circuits, a quantum optical switch is an important element of quantum circuits and quantum networks. Operated at the fundamental limit where a single quantum of light or matter controls another field or material system, it may enable fascinating applications such as long-distance quantum communication, distributed quantum information processing and metrology, and the exploration of novel quantum states of matter. Here, by strongly coupling a photon to a single atom trapped in the near field of a nanoscale photonic crystal cavity, we realize a s…

基于室温平衡外差装置的中红外波段近单光子阿瓦级探测

Near-single-photon atto-watt detection at mid-infrared wavelengths by a room-temperature balanced heterodyne set-up

针对中红外波段单光子探测器需低温工作的问题，提出基于商用光电探测器的室温平衡外差探测方案，实现4.6μm波段阿瓦级（数十光子）灵敏度，为中长波红外量子应用提供可行路径。