Twin-field-based multi-party quantum key agreement

TL;DR

This paper extends the twin-field quantum key distribution protocol to multi-party quantum key agreement, analyzing its security and simulating its practical performance to enable secure multi-party communication over long distances.

Contribution

It introduces a novel multi-party quantum key agreement protocol based on twin-field QKD and provides security analysis and practical performance simulations.

Findings

Protocol achieves secure multi-party key agreement over long distances.

Security is validated through minimum error discrimination analysis.

Performance simulations demonstrate feasibility with optical components.

Abstract

Quantum key distribution (QKD) can secure cryptographic communication between two distant users, as guaranteed by the laws of quantum mechanics rather than computational assumptions. The twin-field scheme, which employs counter-propagated weak coherent light pulses, doubles the secure distance of standard QKD without using quantum repeaters. Here, we study a method to extend the twin-field key distribution protocol to a scheme for multi-party quantum key agreement. We study our protocol's security using a minimum error discrimination analysis and derive the asymptotic key rate based on the entanglement-based source-replacement scheme. We also simulate it on the ANSYS Interconnect platform with optical components to study the protocol's performance in certain practical situations.