A high speed and high efficiency superconducting photon number resolving detector
Tao Xu, Shi Chen, Yajun Chen, Libo Wang, Xiang Li, Xuecou Tu, Xiaoqing Jia, Qingyuan Zhao, Labao Zhang, Lin Kang, Peiheng Wu · Superconductor Science and Technology · 2019
Abstract A series superconducting nanowire single-photon detector is a high performance nanowire array detector that has the potential to reach a high system detection efficiency (SQE), a high counting rate (CR) and photon number resolving functionality. Interconnected with a simplified readout, it shows promise for large scale expansion and has good prospects for future applications in single-photon imaging, quantum optics, quantum computing and deep-space communication. In this paper, we demonstrate a high SQE and CR series superconducting nanowire single-photon detector with an active area of 20 × 20 μ m 2 . The detector shows a maximum SQE of 68% at 1550 nm with a dark count rate of 200 Hz and a wide response wavelength from 1100–2000 nm. It also achieves a CR over 300 MHz at single photon power level and has the capability of resolving photon numbers by up to six photons.