[8p-Z27-1~17] 11.5 Junction and circuit fabrication process, digital applications

△ [8p-Z27-10] Readout of Superconducting Nanowire Single-Photon Detectors using a High-Sensitivity AQFP Comparator

〇(P)Fumihiro China¹, Naoki Takeuchi², Shigehito Miki^1,3, Shigeyuki Miyajima¹, Masahiro Yabuno¹, Hirotaka Terai¹ (1.NICT, 2.Yokohama Natl. Univ., 3.Kobe Univ.)

Keywords:AQFP, SSPD

We have been investigating the readout interfaces for superconducting nanowire single-photon detector (SSPD) arrays using adiabatic quantum-flux-parametron (AQFP). Since AQFP is low-power and low-current driven logic, AQFP is suitable as a post-processing circuit of large-scale SSPD arrays. Furthermore, the high input current sensitivity of AQFP is important for readout of SSPDs with low-switching current for high photon detection efficiency. In this study, we designed a high-sensitivity AQFP comparator using a current transformer. In addition, we experimental evaluated the AQFP comparator with an SSPD in a GM cryocooler. As measurement results, we confirmed that the AQFP comparator can detect the SSPD signal of 4.5 micro ampere with the error late of less than 2%.