A compact multi-pixel superconducting nanowire single-photon detector array supporting gigabit space-to-ground communications

TLDR

Classical and quantum space‑to‑ground communications require highly sensitive receivers to extract information from modulated photons, extending communication distances from near‑Earth to deep space while mitigating strong background noise photons and beam drift in a highly attenuated free‑space channel. The study presents a compact multi‑pixel superconducting nanowire single‑photon detector array that achieves near‑unity detection efficiency, a 1.61 Gcps photon‑counting rate, a dynamic range of 1–24 photons, and four‑quadrant position sensing. The authors built a communication testbed and performed preliminary beam‑tracking experiments using open‑loop scanning to validate the detector’s high‑rate, high‑efficiency, and position‑sensing capabilities. Experiments achieved a 1.5 Gbps 8‑PPM data rate and demonstrated tolerance to 0.8 photons/slot background noise at 120 Mbps, indicating the detector’s suitability for daylight space‑to‑ground communication and future applications.

Abstract

Abstract Classical and quantum space-to-ground communications necessitate highly sensitive receivers capable of extracting information from modulated photons to extend the communication distance from near-earth orbits to deep space explorations. To achieve gigabit data rates while mitigating strong background noise photons and beam drift in a highly attenuated free-space channel, a comprehensive design of a multi-functional detector is indispensable. In this study, we present an innovative compact multi-pixel superconducting nanowire single-photon detector array that integrates near-unity detection efficiency (91.6%), high photon counting rate (1.61 Gcps), large dynamic range for resolving different photon numbers (1–24), and four-quadrant position sensing function all within one device. Furthermore, we have constructed a communication testbed to validate the advantages offered by such an architecture. Through 8-PPM (pulse position modulation) format communication experiments, we have achieved an impressive maximum data rate of 1.5 Gbps, demonstrating sensitivities surpassing previous benchmarks at respective speeds. By incorporating photon number information into error correction codes, the receiver can tolerate maximum background noise levels equivalent to 0.8 photons/slot at a data rate of 120 Mbps—showcasing a great potential for daylight operation scenarios. Additionally, preliminary beam tracking tests were conducted through open-loop scanning techniques, which revealed clear quantitative dependence indicating sensitivity variations based on beam location. Based on the device characterizations and communication results, we anticipate that this device architecture, along with its corresponding signal processing and coding techniques, will be applicable in future space-to-ground communication tasks.