近日，印度哈里什钱德拉研究所的Vivek Pandey与国际信息技术研究所的Arun Kumar Pati等人合作，探究了二粒子量子系统中关联性的速度极限。相关研究成果已于2023年5月25日在国际知名学术期刊《物理评论A》上发表。

在这项研究中，研究人员推导了量子系统在动力学过程中演化时的速度极限与纠缠、Bell-CHSH相关性和量子互信息之间的关联。主要研究结果是关于纠缠单调列的速度极限，即纠缠负度，它适用于任意维度的二粒子量子系统和过程。研究人员还考虑了另一个纠缠单调列，即纠缠并发度。为了验证速度极限的有效性，他们对各种实际感兴趣的量子过程进行了解析和数值计算，包括负度、并发度和Bell-CHSH相关性。他们能够证明，在考虑的实际示例中，他们推导的一些速度极限实际上是可以达到的，因此这些限制可以被认为是紧束缚的。

据悉，量子速度极限是指在给定动力学过程下，量子系统从初始状态演化到最终状态所需的最短时间的限制。这一极限揭示了所期望的状态变换的最快速度，对于量子技术的设计和控制至关重要。

附：英文原文

Title: Speed limits on correlations in bipartite quantum systems

Author: Vivek Pandey, Divyansh Shrimali, Brij Mohan, Siddhartha Das, Arun Kumar Pati

Issue&Volume: 2023/05/25

Abstract: Quantum speed limit is bound on the minimum time a quantum system requires to evolve from an initial state to final state under a given dynamical process. It sheds light on how fast a desired state transformation can take place, which is pertinent for design and control of quantum technologies. In this paper, we derive speed limits on correlations such as entanglement, Bell-CHSH correlation, and quantum mutual information of quantum systems evolving under dynamical processes. Our main result is a speed limit on an entanglement monotone called negativity, which holds for arbitrary-dimensional bipartite quantum systems and processes. Another entanglement monotone which we consider is the concurrence. To illustrate the efficacy of our speed limits, we analytically and numerically compute the speed limits on the negativity, concurrence, and Bell-CHSH correlation for various quantum processes of practical interest. We are able to show that, for practical examples we have considered, some of the speed limits we derived are actually attainable and hence these bounds can be considered to be tight.

DOI: 10.1103/PhysRevA.107.052419

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.107.052419