Differential phase shift quantum secret sharing using twin field

TL;DR

This paper introduces a practical quantum secret sharing protocol that leverages differential phase shift and twin field concepts, significantly enhancing secure key rates over long distances and resisting advanced attacks.

Contribution

It presents a novel QSS protocol that surpasses the linear rate-distance limit and offers improved security against Trojan horse attacks.

Findings

Breaks the linear rate-distance bound, improving secret key rate by three orders of magnitude over 300 km.

Achieves high-efficiency multiparty quantum communication.

Provides security against Trojan horse attacks.

Abstract

Quantum secret sharing (QSS) is essential for multiparty quantum communication, which is one of cornerstones in the future quantum internet. However, a linear rate-distance limitation severely constrains the secure key rate and transmission distance of QSS. Here, we present a practical QSS protocol among three participants based on the differential phase shift scheme and twin field ideas for the solution of high-efficiency multiparty communication task. In contrast to formerly proposed differential phase shift QSS protocol, our protocol can break the linear rate-distance bound, theoretically improving the secret key rate by three orders of magnitude in a 300-km-long fiber. Furthermore, the new protocol is secure against Trojan horse attacks that cannot be resisted by previous differential phase shift QSS.