Sub-shot-noise-limit discrimination of on-off keyed coherent signals via a quantum receiver with a superconducting transition edge sensor

TL;DR

This paper demonstrates a quantum receiver using a superconducting transition edge sensor that surpasses the shot-noise limit in discriminating on-off keyed coherent signals, advancing optical communication technology.

Contribution

Introduces a quantum receiver with a superconducting sensor achieving sub-shot-noise discrimination of coherent signals, improving detection efficiency and error performance.

Findings

Achieved average error below shot-noise limit

High detection efficiency and interference visibility

Effective in a wide range of signal powers

Abstract

We demonstrate a sub-shot-noise-limit discrimination of on-off keyed coherent signals by an optimal displacement quantum receiver in which a superconducting transition edge sensor is installed. Use of a transition edge sensor and a fiber beam splitter realizes high total detection efficiency and high interference visibility of the receiver and the observed average error surpasses the shot-noise-limit in a wider range of the signal power. Our technique opens up a new technology for the sub-shot-noise-limit detection of coherent signals in optical communication channels.