Conventional single-photon detectors at communication wavelengths suffer from low quantum efficiencies and large dark counts. We present a single-photon detection system, operating at communication wavelengths, based on guided-wave frequency upconversion in a nonlinear crystal with an overall system detection efficiency (upconversion + detection) exceeding 46% at 1.56 µm. This system consists of a fiber-pigtailed reverse-proton-exchanged periodically poled LiNbO3 waveguide device in conjunction with a silicon-based single-photon counting module.
© 2005 Optical Society of America
Carsten Langrock, Eleni Diamanti, Rostislav V. Roussev, Yoshihisa Yamamoto, M. M. Fejer, and Hiroki Takesue, "Highly efficient single-photon detection at communication wavelengths by use of upconversion in reverse-proton-exchanged periodically poled LiNbO3 waveguides," Opt. Lett. 30, 1725-1727 (2005)