Operation of Multi-Pixel Radio-Frequency Superconducting Nanowire Single-Photon Detector Arrays

TL;DR

This paper presents an improved RF-SNSPD design enabling multi-pixel detector arrays with reduced complexity and heat load, demonstrating crosstalk-free operation and high resolution using frequency-division multiplexing.

Contribution

The paper introduces a tunable RF-SNSPD design that allows scalable multi-pixel arrays with minimal bandwidth per pixel and no crosstalk, advancing superconducting photon detection technology.

Findings

Demonstrated operation of a two-pixel RF-SNSPD array without crosstalk

Achieved high time, spatial, and photon number resolution

Each pixel requires only 14 MHz bandwidth

Abstract

The concept of the radio-frequency superconducting nanowire single-photon detector (RF-SNSPD) allows frequency-division multiplexing (FDM) of the bias and readout lines of several SNSPDs. Using this method, a multi-pixel array can be operated by only one feed line. Consequently, the system complexity as well as the heat load is significantly reduced. To allocate many pixels into a small bandwidth the quality factor of each device is crucial. In this paper, we present an improved RF-SNSPD design. This new design enables a simple tuning of the quality factor as well as the resonant frequency. With a two-pixel device we have demonstrated the operation without crosstalk between the detectors and showed the time, spatial and photon number resolution. Thereby a single pixel requires only a bandwidth of 14 MHz.