Continuous-variable quantum key distribution protocols over noisy channels

TL;DR

This paper introduces a continuous-variable quantum key distribution protocol using squeezed states and heterodyne detection, achieving higher secret key rates over noisy channels by intentionally adding noise, which enhances noise tolerance.

Contribution

It presents a novel CV-QKD protocol that surpasses existing Gaussian protocols in noisy environments by leveraging noise addition for improved security.

Findings

Higher secret key rates over noisy channels compared to other protocols

Enhanced noise tolerance through intentional noise addition

Provides new physical insights into Gaussian protocol discrepancies

Abstract

A continuous-variable quantum key distribution protocol based on squeezed states and heterodyne detection is introduced and shown to attain higher secret key rates over a noisy line than any other one-way Gaussian protocol. This increased resistance to channel noise can be understood as resulting from purposely adding noise to the signal that is converted into the secret key. This notion of noise-enhanced tolerance to noise also provides a better physical insight into the poorly understood discrepancies between the previously defined families of Gaussian protocols.