Polarization diverse true heterodyne receiver for continuous variable quantum key distribution

TL;DR

This paper introduces a polarization-diverse receiver for continuous variable quantum key distribution that operates reliably without polarization calibration, maintaining security under polarization drift and long-term use.

Contribution

The work presents a novel polarization-diverse receiver architecture that eliminates the need for polarization calibration in CV-QKD systems, enhancing robustness and practicality.

Findings

Achieves theoretical security against coherent attacks

Operates reliably under polarization drift scenarios

Maintains long-term functionality without calibration

Abstract

We present a polarization diverse receiver architecture for continuous variables quantum key distribution. Our receiver architecture forgoes the need for any polarization matching calibrations or feedback loops and is usable in any locally generated local oscillator key distribution system. We demonstrate experimentally that our system is capable of reliably achieving theoretical security against coherent attacks, even under very adverse random polarization drift scenarios, where the single polarization channels are unable to achieve security, and is capable of functioning for long periods of time.