近日，清华大学低维量子物理国家重点实验室的龙桂鲁及其研究团队取得一项新进展。经过不懈努力，他们实现基于蝴蝶网络的交叉量子同态加密。相关研究成果已于2024年6月12日在国际知名学术期刊《物理评论A》上发表。

在本文中，研究人员提出了一种基于蝴蝶网络的交叉量子同态加密方案，在该方案中，每个接收者都能以完美的保真度接收到评估的量子态。蝴蝶网络发送端之间的纠缠态被预共享，并使用贝尔基测量值对量子明文进行加密。同时使用经典通道和量子通道，可以在蝴蝶网络上完美地、交叉地完成量子明文的同态评估。

该方案成功解决了瓶颈节点交叉评估的难题，显著提升了评估效率，并有效增加了网络总吞吐量。同时，研究人员运用蝴蝶网络设计了多样化的量子评估电路，为实验实施提供了明确的蓝图。此外，他们还对该方案的安全性进行了分析。

据悉，量子同态加密对未经授权的参与者隐藏了量子信息，同时仍然允许他们对加密的量子信息进行计算。

附：英文原文

Title: Cross quantum homomorphic encryption based on the butterfly network

Author: Xing-bo Pan, Yu-Ting Lei, Xiang-jie Li, Xiu-bo Chen, Gui-lu Long

Issue&Volume: 2024/06/12

Abstract: Quantum homomorphic encryption hides quantum information from unauthorized participants while still allowing them to perform calculations on encrypted quantum information. In this paper, we propose a cross quantum homomorphic encryption scheme based on the butterfly network, in which every receiver can receive the evaluated quantum state with perfect fidelity. The entangled states between senders of the butterfly network are preshared, and the Bell basis measurements are used to encrypt the quantum plaintext. With both classical and quantum channels, the homomorphic evaluation of quantum plaintext can be completed on the butterfly network perfectly and crossly. Our scheme solves a bottleneck problem of cross evaluation at the bottleneck nodes, and improves the evaluation efficiency and total network throughput. In addition, we have designed quantum circuits according to different quantum evaluations with a butterfly network, which provide a basic blueprint for experimental implementation. The security of the scheme is also analyzed.

DOI: 10.1103/PhysRevA.109.062606

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.109.062606