Amorphous superconducting nanowire single-photon detectors integrated with nanophotonic waveguides

M Häußler,M A Wolff,M Yu Mikhailov,C Schuck

doi:10.1063/5.0004677

Abstract

Future applications in integrated quantum photonics will require large numbers of efficient, fast, and low-noise single-photon counters. Superconducting nanowire single-photon detectors made from amorphous material systems are best suited to meet these demands, but the integration with nanophotonic circuits has remained a challenge. Here, we show how amorphous molybdenum silicide (MoSi) nanowires are integrated with nanophotonic silicon nitride waveguides in traveling wave geometry. We found a saturated on-chip detection efficiency of (73 ± 10) % for telecom wavelength photons and the sub-10 Hz dark count rate at a temperature of 2.1 K, which allows for operation in robust, compact, and economic cryogenic systems. Applications requiring fast counting will benefit from the sub-5 ns recovery times of our devices that we combine with 135 ps timing accuracy. Achieving this performance with waveguide-integrated amorphous superconductors is an important step toward enabling high yield fabrication of competitive single-photon detectors on a large variety of nanophotonic material systems.

Highlights

Superconducting nanowire single-photon detectors (SNSPDs) offer distinguished measurement capabilities in modern quantum technology applications such as quantum communication,1,2 quantum simulations,3 and quantum sensing.4,5 The advantages of SNSPDs over other single-photon detector technologies are their superior detection efficiency from the UV to mid-IR wavelengths, low noise performance, high speed, and timing accuracy
While conventional SNSPDs are typically illuminated under normal incidence from an optical fiber, SNSPDs can be integrated with nanophotonic waveguides in traveling wave geometry, where photons are absorbed in a nanowire along their direction of propagation
We consider molybdenum silicide (MoSi), a interesting candidate, because promising performance in the telecom wavelength regime has recently been observed with the conventional meandershaped MoSi-SNSPD at temperatures above 2 K,25–30 which allows for operation in state-of-the-art cost-effective and stable cryogenic systems

Summary

Introduction

Superconducting nanowire single-photon detectors (SNSPDs) offer distinguished measurement capabilities in modern quantum technology applications such as quantum communication,1,2 quantum simulations,3 and quantum sensing.4,5 The advantages of SNSPDs over other single-photon detector technologies are their superior detection efficiency from the UV to mid-IR wavelengths, low noise performance, high speed, and timing accuracy.6.

Results

Conclusion