近日，德国锡根大学的Lina Vandré与Otfried Gühne合作并取得一项新进展。经过不懈努力，他们实现超图态的纠缠纯化。相关研究成果已于2023年12月14日在国际知名学术期刊《物理评论A》上发表。
在本文中，研究人员提出了超图态纯化的优化协议，这些超图态形成了从几个角度相关的多量子比特态族。研究人员用图形语言重新制定现有的纯化协议。这将允许系统优化，研究人员提出了三个方向的改进。首先，可以根据各方的顺序优化协议的序贯。其次，可以使用自适应方案，其中在协议中获得的测量结果用于修改协议。最后，可以在效率方面改进协议，需要更少的噪声态副本来达到某个目标状态。
据悉，纠缠纯化是量子信息处理中的一种原语，它通过局部操作和经典通信，将几个含噪量子态副本提取成几个高质量的近纯态副本。在多粒子情况下，由于存在许多不相等形式的纯态纠缠，需要针对不同的目标态定制纯化方案，因此纠缠纯化的任务非常复杂。
附：英文原文
Title: Entanglement purification of hypergraph states
Author: Lina Vandré, Otfried Gühne
Issue&Volume: 2023/12/14
Abstract: Entanglement purification describes a primitive in quantum information processing, where several copies of noisy quantum states are distilled into a few copies of nearly pure states of high quality via local operations and classical communication. Especially in the multiparticle case, the task of entanglement purification is complicated, as many inequivalent forms of pure state entanglement exist and purification protocols need to be tailored for different target states. In this paper we present optimized protocols for the purification of hypergraph states, which form a family of multiqubit states that are relevant from several perspectives. We start by reformulating an existing purification protocol in a graphical language. This allows for systematical optimization and we present improvements in three directions. First, one can optimize the sequences of the protocol with respect to the ordering of the parties. Second, one can use adaptive schemes, where the measurement results obtained within the protocol are used to modify the protocols. Finally, one can improve the protocol with respect to the efficiency, requiring fewer copies of noisy states to reach a certain target state.
DOI: 10.1103/PhysRevA.108.062417
Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.108.062417
来源：科学网 小柯机器人