Superconducting nanowire single photon detector at 532 nm and demonstration in satellite laser ranging

TL;DR

This paper presents the design, fabrication, and successful satellite laser ranging demonstration of superconducting nanowire single-photon detectors at 532 nm, achieving high efficiency and precise distance measurement for space applications.

Contribution

It introduces a novel SNSPD optimized for 532 nm with high efficiency and demonstrates its application in satellite laser ranging with high precision.

Findings

75% detection efficiency at <0.1 Hz dark count rate

Successful satellite laser ranging with 8 mm depth precision

Demonstration at a satellite 3,000 km away

Abstract

Superconducting nanowire single-photon detectors (SNSPDs) at a wavelength of 532 nm were designed and fabricated aiming to satellite laser ranging (SLR) applications. The NbN SNSPDs were fabricated on one-dimensional photonic crystals with a sensitive-area diameter of 42 um. The devices were coupled with multimode fiber (phi=50um) and exhibited a maximum system detection efficiency of 75% at an extremely low dark count rate of <0.1 Hz. An SLR experiment using an SNSPD at a wavelength of 532 nm was successfully demonstrated. The results showed a depth ranging with a precision of ~8.0 mm for the target satellite LARES, which is ~3,000 km away from the ground ranging station at the Sheshan Observatory.