Improving the readout circuit of superconducting nanowire single-photon detectors

Clinton Cahall, Daniel J. Gauthier, Jungsang Kim

We study an electrical readout scheme for superconducting nanowire single photon detectors using commercial off-the-shelf amplifiers operating at cryogenic temperatures. Low power consumption and improved noise performance enable multichannel readout circuit solution with high timing resolution.

Adam N. McCaughan

Berggren, Anant, Baek +11 more

Qingyuan Zhao, Tao Jia, Min Gu +6 more

Counting rates of superconducting nanowire single-photon detectors are usually estimated at hundreds of MHz by their kinetic-inductive reset time. This maximum is also limited by capacitor coupling effects in conventional readout circuits. In this Letter, we design and demonstrate an improved readout circuit that reduces the reset time and removes circuit limits. The counting rate at the 3 dB compression point is increased by four times for a large active area detector. We also discuss nonlinear dependences of the counting rate on the incident continuous-wave optical power and give a numerical model to explain our observations.

Taro Yamashita, Shigehito Miki, Hirotaka Terai +2 more

We demonstrate the successful operation of a multielement superconducting nanowire single-photon detector (SSPD) array integrated with a single-flux-quantum (SFQ) readout circuit in a compact 0.1 W Gifford-McMahon cryocooler. A time-resolved readout technique, where output signals from each element enter the SFQ readout circuit with finite time intervals, revealed crosstalk-free operation of the four-element SSPD array connected with the SFQ readout circuit. The timing jitter and the system detection efficiency were measured to be 50 ps and 11.4%, respectively, which were comparable to the performance of practical single-pixel SSPD systems.

Xiaolong Hu, Yuhao Cheng, Chao Gu +2 more