华南师范大学张旦波团队实现了通过测量数字量子模拟器上的Holevo信息揭示量子算子置乱。这一研究成果于2025年7月1日发表在《物理评论A》杂志上。

量子算子置乱描述了海森堡演化图像中局部算子向整个系统的扩展，通常用算子大小的增长来量化。研究组提出了一种利用算子的Holevo信息局部区分算子信息的量子算子置乱度量方法。并证明了算子的大小与算子的一类特殊的Holevo信息密切相关。

此外，研究组还提出了一种可行的基于随机态的数字量子模拟器算子Holevo信息测量协议。对于混合场Ising模型，他们的数值模拟表明，通过测量Holevo信息的时空模式可以将可积系统与混沌系统区分开来。此外还发现，为了恢复可积系统Holevo信息的时间振荡行为，需要减小误差，这是区别于混沌系统的一个关键特征。他们的工作为从算子Holevo信息的角度理解信息置乱和量子混沌提供了新的视角。

附：英文原文

Title: Revealing quantum operator scrambling via measuring Holevo information on digital quantum simulators

Author: Bin Sun, Geng-Bin Cao, Xi-Dan Hu, Dan-Bo Zhang

Issue&Volume: 2025/07/01

Abstract: Quantum operator scrambling describes the spreading of local operators into the whole system in the picture of Heisenberg evolution, which is often quantified by the operator size growth. Here we propose a measure of quantum operator scrambling via Holevo information of operators, by taking its capacity to distinguish operator information locally. We show that the operator size is closely related to a special kind of Holevo information of operators. Moreover, we propose a feasible protocol for measuring Holevo information of operators on digital quantum simulators based on random states. For the mixed-field Ising model, our numerical simulations show that the integrable system can be told apart from the chaotic system by measuring the spatial-temporal patterns of Holevo information. Furthermore, we find that error mitigation is required to restore the time-oscillation behavior of Holevo information for the integrable system, a crucial feature distinct from the chaotic one. Our work provides a new perspective to understand the information scrambling and quantum chaos from aspects of Holevo information of operators.

DOI: 10.1103/s1t6-6brz

Source: https://journals.aps.org/pra/abstract/10.1103/s1t6-6brz