A 16-pixel NbN nanowire single photon detector coupled with 300 micrometer fiber

TL;DR

This paper presents a 4x4 NbN SNSPD array coupled with a 300 micrometer fiber, achieving high efficiency and compact design, demonstrating the feasibility of large-area superconducting photon detectors for advanced quantum applications.

Contribution

First demonstration of a 16-pixel NbN SNSPD array coupled with 300 micrometer fiber, showing high efficiency and compactness for large-area photon detection.

Findings

Quantum efficiency of 94.5% achieved

System efficiency of 46% without polarization optimization

System time resolution of 92 ps

Abstract

Niobium Nitride (NbN) nanowire is the most popular detection material of superconducting nanowire single photon detectors (SNSPDs) for high repetition rate and high efficiency. However, it has been assumed to be difficult for fabricating SNSPDs with arrays over large area, which are critical components of quantum imaging, linear optical quantum computing, satellite laser ranging, and high-speed quantum key distribution. This paper reported a 4*4 pixel NbN SNSPDs array with an equivalent receiving aperture of 300 micrometer associated with beam compression technology, which is the first NbN SNSPD coupled by 300 micrometer fiber according to our knowledge. The designed pixel was compact with a filling factor of 98.5%, resulting in a high quantum efficiency of 94.5%, a system efficiency of 46% for photons coupled from 300 micrometer fiber without optimizing polarization, and a system time resolution of 92 ps. This work demonstrates the feasibility of a large SNSPDs array, and paves the way for developing efficient photon camera with NbN nanowires.