Temperature-Dependent Characterization of Large-Area Superconducting Microwire Array with Single-Photon Sensitivity in the Near-Infrared

TL;DR

This study investigates the temperature-dependent performance of a large-area superconducting microwire single-photon detector array, revealing key efficiency, timing, and dark count characteristics crucial for dark matter detection applications.

Contribution

It provides the first detailed temperature-dependent analysis of a large-area WSi superconducting microwire detector array, including dark count correlations relevant for low-background experiments.

Findings

Saturated detection efficiency from 635 nm to 1650 nm

Time jitter of about 160 ps at 1060 nm

Low dark count rate of approximately 10^{-2} Hz

Abstract

Superconducting nanowire single photon detectors (SNSPDs) are a leading detector technology for time-resolved single-photon counting from the ultraviolet to the near-infrared regime. The recent advancement in single-photon sensitivity in micrometer-scale superconducting wires opens up promising opportunities to develop large area SNSPDs with applications in low background dark matter detection experiments. We present the first detailed temperature-dependent study of a 4-channel $1\times1$ mm$^{2}$ WSi superconducting microwire single photon detector (SMSPD) array, including the internal detection efficiency, dark count rate, and importantly the coincident dark counts across pixels. The detector shows saturated internal detection efficiency for photon wavelengths ranging from 635 nm to 1650 nm, time jitter of about 160 ps for 1060 nm photons, and a low dark count rate of about $10^{-2}$ Hz. Additionally, the coincidences of dark count rate across pixels are studied for the first time in detail, where we observed an excess of correlated dark counts, which has important implications for low background dark matter experiments. The results presented is the first step towards characterizing and developing SMSPD array systems and associated background for low background dark matter detection experiments.