Superconducting nanowire single-photon detectors: physics and applications

TL;DR

This review covers the physics, design evolution, performance improvements, limitations, and applications of superconducting nanowire single-photon detectors, highlighting their rapid development and potential in quantum and sensing technologies.

Contribution

It provides a comprehensive overview of SNSPD physics, design advancements, performance metrics, limitations, and practical applications, capturing the state of this emerging technology.

Findings

High efficiency and low dark counts achieved

Performance improvements over time documented

Potential applications in quantum cryptography and sensing

Abstract

Single-photon detectors based on superconducting nanowires (SSPDs or SNSPDs) have rapidly emerged as a highly promising photon-counting technology for infrared wavelengths. These devices offer high efficiency, low dark counts and excellent timing resolution. In this review, we consider the basic SNSPD operating principle and models of device behaviour. We give an overview of the evolution of SNSPD device design and the improvements in performance which have been achieved. We also evaluate device limitations and noise mechanisms. We survey practical refrigeration technologies and optical coupling schemes for SNSPDs. Finally we summarize promising application areas, ranging from quantum cryptography to remote sensing. Our goal is to capture a detailed snapshot of an emerging superconducting detector technology on the threshold of maturity.