Full polarization control for fiber optical quantum communication systems using polarization encoding

TL;DR

This paper presents a real-time polarization control system for fiber optical quantum communication that achieves complete polarization state control with minimal error and fast response times, enhancing quantum data transmission reliability.

Contribution

The study introduces a novel closed-loop polarization control method using multiplexed reference signals, demonstrating both theoretical and experimental effectiveness in quantum communication.

Findings

Achieves polarization control with less than 0.045% quantum bit error rate

Response times are under 10 milliseconds

Minimal noise introduction in the quantum channel

Abstract

A real-time polarization control system employing two nonorthogonal reference signals multiplexed in either time or wavelength with the data signal is presented. It is shown, theoretically and experimentally, that complete control of multiple polarization states can be attained employing polarization controllers in closed-loop configuration. Experimental results show that negligible added penalties, corresponding to an average added optical Quantum Bit Error Rate of 0.044%, can be achieved with response times smaller than 10 ms, without significant introduction of noise counts in the quantum channel.