基于钛相变边缘传感器的超导单光子探测器特性

Characteristics of Ti transition-edge sensor based superconducting single-photon detectors

研究了基于钛TES的超导单光子探测器的特性,器件尺寸范围为5μm×5μm到20μm×20μm,集成光学腔体后在1550 nm波长实测的系统探测效率最高达到72%,最佳能量分辨率为0.26 eV。在此基础上,采用二流体模型提取了基于钛TES的超导单光子探测器的特性参数(包括温度灵敏度、电流灵敏度、热容等),并模拟计算了基于钛TES的超导单光子探测器的响应时间和能量分辨率,与实验结果完全吻合。结果表明优化探测器尺寸和临界温度,可以同时达到高探测效率和高能量分辨率,实现光子数可分辨的高性能单光子探测器。

Ti TES-based superconducting single-photon detectors with different dimensions between 5μm×5μm and 20μm×20μm were developed.The measured system detection efficiency(η)is 72%at 1550 nm,and energy resolution(ΔE)is 0.26 eV by integrating an optical cavity during the TES fabrication.Based on the two-fluid model,we extract the key parameters(i.e.,temperature sensitivity,current sensitivity,heat capacity,et.al)of Ti TES-based superconducting single-photon detectors with different dimensions,and calculate the effective response time andΔE,which are consistent with the measured ones.The obtained results show that it’s possible to realize highηandΔE by optimizing TES dimension and critical temperature,paving the way for high performance single-photon detectors at telecommunication band.