Experimental demonstration of relative temporal multiplexing

Interference between single photons lies at the heart of linear optical quantum computing (LOQC). However, the lack of deterministic single photon sources hinders the large-scale experimental demonstration and its practical applications, as the probability to generate N single photons simultaneously (denoted by N-photon hereafter) decreases exponentially with the increasing number of single photon sources [1]. Multiplexing is the leading proposal to overcome this challenge by relocating single photon from different modes to one fixed mode. The theoretical work [2] indicates that the relative time multiplexing (RMUX) scheme could significantly enhance this probability and meanwhile reduce the requirements of multiplexing system, such as switching speed and system complexity. In this paper, RMUX of two heralded single photon sources is demonstrated for the first time. We observe around 90% enhancement on the heralded photon pair rate, compared to the standard time multiplexing (SMUX) scheme [3].