Coherent detection schemes for subcarrier wave continuous variable quantum key distribution

TL;DR

This paper explores and experimentally validates various coherent detection methods, including homodyne and heterodyne schemes, for enhancing subcarrier wave quantum key distribution systems, focusing on extracting information from quadrature phase-coded signals.

Contribution

It introduces models for homodyne and heterodyne detection in SCW QKD and demonstrates their practical feasibility through experiments.

Findings

Homodyne and heterodyne detection models are effective for SCW QKD.

Experimental results confirm the practicality of the proposed detection schemes.

Enhanced information extraction from quadrature phase-coded signals in SCW QKD.

Abstract

We examine different methods to implement coherent detection in the subcarrier wave quantum key distribution (SCW QKD) systems. For classical wavefields, we present the models describing homodyne-type and heterodyne-type coherent detection schemes needed to extract information from the quadrature phase-coded multimode signals used in SCW QKD. Practical feasibility of the proposed schemes is corroborated by the experiments.