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Low-Noise PPLN-based Single-Photon Detector



Hai Xu, Lijun Ma, Oliver T. Slattery, Xiao Tang


This paper describes the detection of single photons, which have been transmitted through standard fiber at the telecom wavelength of 1310 nm. Following transmission, the 1310-nm photon is up-converted to 710 nm in a periodical-poled LiNbO3 (PPLN) waveguide and then detected by a silicon-based avalanche photo diode (Si-APD). The overall detection efficiency of the detector is 20%. We have also characterized the sensitivity of the PPLN's efficiency to temperature and wavelength changes. We focused on the noise property of the up-conversion detector. Without classical channel co-propagation, the dark count rate is 2.2 kHz, which is lower than current up-conversion detectors by more than one order of magnitude. The up-conversion detector is then applied to a QKD system, which is characterized and is shown to have a very strong performance.
Society of Photographic Instrumentation Engineers (SPIE) Optics East


PPLN, Quantum Key Distribution (QKD), single photon detector


Xu, H. , Ma, L. , Slattery, O. and Tang, X. (2007), Low-Noise PPLN-based Single-Photon Detector, Society of Photographic Instrumentation Engineers (SPIE) Optics East, [online], (Accessed June 18, 2024)


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Created February 12, 2007, Updated October 12, 2021