A bright source of telecom single photons based on quantum frequency conversion

On-demand indistinguishable single-photon sources are essential for quantum networking and communication. Semiconductor dots among the most promising candidates, but their typical emission wavelength renders them unsuitable use in fiber networks. Here, we present frequency conversion of near-infrared photons from a bright dot to telecommunication C-band, allowing integration with existing architectures. We custom-built, tunable 2400 nm seed laser convert single 942 1550 difference-frequency generation process. achieve an end-to-end efficiency ?35%, demonstrate count rates approaching 1 MHz at g ( 2 ) 0 = 0.043 ), Hong-Ou-Mandel (HOM) visibilities 60%. expect this scheme be preferable directly emitting telecom wavelengths fiber-based networking.