标题： 基于d级GHZ态的多方量子隐私比较 显示英文标题

标题： Multi-party quantum privacy comparison of size based on d-level GHZ states

摘要： 量子隐私比较(QPC)在秘密投票选举、私人拍卖等方面起着重要作用。 到目前为止，已经提出了许多多方QPC(MQPC)协议来比较$k(k\geq 3)$个参与者的相等性。 然而，很少有MQPC用于比较其隐私的大小或值。 在本文中，我们提出了一种MQPC协议，通过该协议，任何$k(k\geq 3)$个参与者只需执行一次协议即可比较其隐私的大小。 所提出的MQPC协议以$d-level$GHZ态作为量子资源，并引入了一个半诚实的$TP$来帮助参与者确定其隐私之间的关系。 此外，仅涉及单粒子单位变换和测量，参与者不需要事先彼此共享共同密钥，这使得所提出的协议更加高效。 分析表明，我们的协议在理论上可以抵御内部和外部攻击。 显示英文摘要

摘要： Quantum privacy comparison(QPC) plays an important role in secret ballot elections, private auctions and so on. To date, many multi-party QPC(MQPC) protocols have been proposed to compare the equality of $k(k\geq 3)$ participants. However, there are few examples of MQPC used to compare the sizes or values of their privacies. In this paper, we propose a MQPC protocol by which any $k(k\geq 3)$ participants can compare the sizes of their privacies with executing the protocol just once. The proposed MQPC protocol takes the $d-level$ GHZ states as quantum resources, and a semi-honest $TP$ is introduced to help the participants to determine the relationship of their privacies. Further more, only single-particle unitary transformations and measurements are involved, and the participants need not to share common secrets with each other beforehand which makes the proposed protocol much more efficient. Analysis shows that our protocol is secure against internal and external attack in theory.