Symmetric Device-Independent Quantum Key Distribution Against General Attack

TL;DR

This paper introduces a symmetric device-independent quantum key distribution protocol that leverages Holevo limit and von Neumann entropy properties to securely bound eavesdropper information, ensuring security against general attacks.

Contribution

It presents a novel symmetric DIQKD protocol that uses statistical CHSH measurements to guarantee security against broad attack strategies, aligning with Ekert91's security basis.

Findings

Eve's information gain can be bounded using CHSH polynomial S.

The protocol achieves security comparable to Ekert91.

Eavesdropping can be inferred from measurement statistics.

Abstract

A symmetric device-independent quantum key distribution (DIQKD) protocol is proposed in this paper, with Holevo limit and subadditivity of von Neumann entropy, one can bound Eve's ability with collective attack. Together with symmetry of this protocol, the state Eve prepared for Alice and Bob, and at the same time, her eavesdropping on Alice's and Bob's measurements can be definitely inferred at the assumption that Eve aims at maximizing her information gain. The optimal state under this circumstance can be solely bounded with Alice and Bob's statistical results on the quantity of Clauser-Horne-Shimony-Holt (CHSH) polynomial $S$, that is, our symmetric DIQKD has the same secure basis as that of Ekert91 protocol.