RATIO-ADJUSTABLE SINGLE PHOTON BEAM SPLITTER BASED ON COLD ATOM STORAGE

摘要

A ratio-adjustable single photon beam splitter based on cold atom storage, comprising: a two-dimensional magneto-optical trap (1) used for receiving a first optical signal to be split (2a); and a coupled beam (3) incident at a certain angle with the first optical signal (2a) to the two-dimensional magneto-optical trap (1). The storage time of the two-dimensional magneto-optical trap (1) can be adjusted by controlling the switching time of the coupled beam (3), then the ratio of the number of photons in a storage part to the number of photons in a leakage part of the first optical signal (2a) is adjusted, and the beam splitting ratio can also be adjusted by controlling the optical thickness of an alkali metal atomic group trapped in the two-dimensional magneto-optical trap (1). The single photon beam splitter is simple in structure and easy to construct, and has a bandwidth of up to 100 MHz; and the beam splitting ratio can be adjusted according to need in various ways.