Multichannel SNSPD system with high detection efficiency at telecommunication wavelength

We developed a four-channel superconducting nanowire single-photon detector system based on a Gifford-McMahon cryocooler. All channels showed a system detection efficiency (DE) (at a 100 Hz dark-count rate) higher than 16% at 1550 nm wavelength, and the best channel showed a system DE of 21% and 30% at 1550 and 1310 nm wavelength, respectively. (C) 2010 Optical Society of America