# Single-State Multi-Party Quantum Key Agreement with Single-Particle Measurement

## TL;DR

This paper introduces a new quantum key agreement protocol that uses single-particle measurements and is more efficient than previous methods.

## Contribution

The novel contribution is a single-state multi-party quantum key agreement protocol that improves efficiency and eliminates complex operations.

## Key findings

- The protocol uses a single multi-particle entangled state as a quantum resource.
- It achieves higher qubit efficiency and requires fewer qubits for transmission.
- The protocol is secure against internal and external attacks.

## Abstract

In this study, we propose a single-state multi-party quantum key agreement (MQKA) protocol with single-particle measurement. Firstly, a single-state three-party quantum key agreement protocol with single-particle measurement is introduced, followed by a security analysis that validated its capability to resist potential internal and external attacks. Furthermore, we utilize multi-particle entangled states to present a multi-party version of the single-state multi-party quantum key agreement with single-particle measurement. In comparison to previous MQKA protocols, our approach presents the following advantages: it employs one kind of multi-particle entangled state as the quantum resource; eliminates the need for entanglement swapping techniques, unitary operations, or pre-shared keys between participants; uses only the X measurement basis and Z measurement basis; transmits fewer qubits; consumes fewer qubits; and has higher qubit efficiency.