Towards practical security of continuous-variable quantum key distribution

TL;DR

This paper examines the gap between theoretical security proofs of continuous-variable quantum key distribution and practical experimental conditions, proposing potential workarounds and highlighting unresolved issues.

Contribution

It analyzes practical limitations of current security proofs for CV QKD and discusses experimentally feasible methods to assess security.

Findings

Identifies assumptions in security proofs that are hard to meet experimentally

Proposes workarounds for practical security assessment

Highlights unresolved issues in current security frameworks

Abstract

Rigorous mathematical proofs of the security of continuous-variable quantum key distribution (CV QKD) have been obtained recently. Unfortunately, these security proofs rely on assumptions that are hardly met in experimental practice. Here I investigate these issues in detail, and discuss experimentally-friendly workarounds to assess the security of CV QKD. The aim of this paper is to show that there are hidden and unsolved issues and to indicate possible partial solutions. To provide a complete and rigorous mathematical security proof is out of the scope of this contribution.