Suppressing the Errors due to Mode Mismatch for M-ary PSK Quantum Receivers by Photon-Number-Resolving Detector

TL;DR

This paper analyzes a M-ary PSK quantum receiver and demonstrates that using photon-number-resolving detectors significantly reduces errors caused by mode mismatch, improving receiver performance under realistic conditions.

Contribution

It introduces a method to suppress mode mismatch errors in quantum receivers by replacing on-off detectors with photon-number-resolving detectors, considering practical detector imperfections.

Findings

Photon-number-resolving detectors reduce mode mismatch errors.

Mode mismatch has the largest impact among practical factors.

Using PNRD improves the error probability of the receiver.

Abstract

A M-ary phase shift keying (PSK) quantum receiver consisting of displacement operations, photon counting, and electrical feed-back adaptive measurements is analyzed with a realistic model considering the effects of the sub-unity quantum efficiency and the dark counts of single-photon detectors, as well as the transmittance and the mode mismatch of beam splitters. Among these factors, the mode mismatch has the greatest impact on the error probability of the receiver with on-off detectors. The errors due to mode mismatch can be suppressed effectively by using photon-number-resolving detectors (PNRD) instead of on-off detectors.