Photon-Counting Spectrometers Based on Superconducting Nanowire Single-Photon Detectors

Abstract

Optical spectrum analysis provides a wealth of information about the physical world. Throughout the development of optical spectrum analysis, sensitivity has been one of the major topics and has become essential in applications dealing with faint light. Various high-sensitivity optical detection technologies have been applied in optical spectrum analysis to enhance its sensitivity to single-photon level. As an emerging single-photon detection technology, superconducting nanowire single-photon detectors (SNSPDs) have many impressive features such as high detection efficiency, broad operation bandwidth, small timing jitter, and so on, which make them promising for enhancing the performance of optical spectral analysis. Diverse schemes for photon-counting spectrometers based on SNSPDs have been demonstrated. This article reviews these impressive works and prospects for the future development of this technology. Further breakthroughs can be expected in its theories, device performance, applications, and combinations with in-sensor computing, promoting it to be a mature and versatile solution for optical spectrum analysis on ultra-faint light.