Authenticated quantum key agreement based on cluster states against collective noise

Quantum key agreement (QKA) is an important branch of quantum cryptography. Particles are easily affected by noise in quantum channel transmission, which provides a cover for eavesdropper Eve to attack maliciously and eventually leads to the protocol failure. In this paper, based on the properties of four-particle cluster states and their entanglement swapping, two authenticated two-party QKA protocols that can resist collective noise (collective-dephasing noise and collective-rotation noise) by using CZ, CNOT, and Pauli operations are designed, respectively. Besides, both parties can authenticate each other's identities, which makes our protocol more secure. In addition, security analysis shows that these two protocols can resist various attacks from inside and outside, such as participant attacks and entangle-measure attacks.