The quantum private comparison aims to make the size comparison of two participants’ private information without leaking the private data of their own with quantum mechanism. In this paper, different from the current method of using single particle or entangled state as the information carrier, a novel two-party quantum private comparison protocol is firstly proposed via quantum walks on circle. In the protocol, a third party is assumed to be semi-honest and allowed to misbehave on his own, but cannot conspire with either of the two dishonest participants and obtain the participants’ private information. The protocol adopts the two-particle quantum walks state on circle rather than entangled state as the initial quantum resource and only needs measurement and quantum walks operator without the unitary operation and quantum entanglement swapping. The two-particle state is transferred as a whole among different parties, which reduces the protocol complexity and avoids the chance of being attacked. It can implement the equality comparison of private information, but also the size comparison. Security analyses show that this protocol is resistant to the external and internal malicious attacks, which can also determine the disputes over the judgment result of the third party. Compared with other quantum private comparison protocols, the proposed protocol has better flexibility and universality.

量子私有比较的目的是对两个参与者的私有信息进行大小比较，而不会通过量子机制泄漏他们自己的私有数据。本文与目前使用单粒子或纠缠态作为信息载体的方法不同，首先提出了一种基于量子步态的两方量子私有比较协议。在该协议中，假定第三方是半诚实的，并且允许自己行为不当，但不能与两个不诚实的参与者中的任何一个合谋，也无法获得参与者的私人信息。该协议采用圆上的两粒子量子游动状态而不是纠缠态作为初始量子资源，只需要测量和量子游动算子即可，而无需统一运算和量子纠缠交换。两粒子状态作为一个整体在不同的参与者之间转移，这降低了协议的复杂性并避免了被攻击的机会。它可以实现私有信息的相等性比较，也可以实现大小比较。安全分析表明，该协议可以抵抗内部和外部的恶意攻击，也可以确定与第三方判断结果有关的争议。与其他量子专用比较协议相比，该协议具有更好的灵活性和通用性。安全分析表明，该协议可以抵抗内部和外部的恶意攻击，也可以确定与第三方判断结果有关的争议。与其他量子专用比较协议相比，该协议具有更好的灵活性和通用性。安全分析表明，该协议可以抵抗内部和外部的恶意攻击，也可以确定与第三方判断结果有关的争议。与其他量子专用比较协议相比，该协议具有更好的灵活性和通用性。