Unconditional security proof of long-distance continuous-variable quantum key distribution with discrete modulation

TL;DR

This paper introduces a secure continuous-variable quantum key distribution protocol using discrete modulation and reverse reconciliation, enabling long-distance secret key sharing with proven unconditional security.

Contribution

It provides the first unconditional security proof for a long-distance CV-QKD protocol with discrete modulation and reverse reconciliation.

Findings

Protocol is unconditionally secure.

Enables long-distance quantum key distribution.

Efficient at very low signal-to-noise ratios.

Abstract

We present a continuous-variable quantum key distribution protocol combining a discrete modulation and reverse reconciliation. This protocol is proven unconditionally secure and allows the distribution of secret keys over long distances, thanks to a reverse reconciliation scheme efficient at very low signal-to-noise ratio.