Authentication of Continuous-Variable Quantum Messages

TL;DR

This paper presents the first quantum authentication scheme for continuous-variable states, adapting a discrete-variable approach with enhanced flexibility, and provides a security proof including a continuous-variable Pauli Twirl.

Contribution

It introduces a novel continuous-variable quantum authentication scheme based on trap states, extending discrete-variable methods and offering a security proof.

Findings

First continuous-variable quantum authentication scheme introduced

Security proof established using a continuous-variable Pauli Twirl

Scheme allows flexible choice of trap states

Abstract

We introduce the first quantum authentication scheme for continuous-variable states. Our scheme is based on trap states, and is an adaptation of a discrete-variable scheme by Broadbent et al. (arXiv:1211.1080), but with more freedom in choosing the number of traps. We provide a security proof, mostly following the approach of Broadbent and Wainewright (arXiv:1607.03075). As a necessary ingredient for the proof we derive the continuous-variable analogue of the Pauli Twirl.