对称随机Clifford电路中的量子Mpemba效应
The quantum Mpemba effect in symmetric random Clifford circuits
- The University of Electro-Communications（电气通信大学）
- SISSA and INFN（的里雅斯特高等研究学院和意大利国家核物理研究所）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
该研究在对称随机Clifford电路中证实量子Mpemba效应，通过映射到电荷守恒自动机，揭示初始对称性破缺越强，粒子相遇越频繁，从而加速对称性恢复的微观机制。
AI中文摘要：
量子Mpemba效应是一种反直觉现象，即初始离平衡更远的量子态比初始更接近平衡的量子态弛豫得更快。我们在具有守恒U(1)电荷的随机Clifford电路中展示了这一效应，利用纠缠不对称性来表征通过动力学对称性恢复的弛豫过程。精确数值模拟表明，初始更不对称的态可以变得比初始较不对称的态在局部更对称。我们通过将动力学映射到电荷守恒的量子自动机来解释这一行为，在该自动机中，纠缠不对称性的衰减由根据对称简单排斥过程演化的两种粒子种类之间的相遇统计所控制。这一映射给出了纠缠不对称性的解析表达式，并为量子Mpemba效应提供了一个简单的微观机制：更强的初始对称性破缺对应于更密集的粒子构型，这增加了粒子相遇的频率，从而加速了对称性恢复。
英文摘要：
The quantum Mpemba effect is the counterintuitive phenomenon whereby a quantum state initially farther from equilibrium relaxes faster than one initially closer to it. We demonstrate this effect in random Clifford circuits with a conserved $\mathrm{U}(1)$ charge, using the entanglement asymmetry to characterize relaxation through dynamical symmetry restoration. Exact numerical simulations show that an initially more asymmetric state can become locally more symmetric than an initially less asymmetric one. We explain this behavior by mapping the dynamics onto a charge-conserving quantum automaton, in which the decay of the entanglement asymmetry is controlled by the statistics of encounters between two particle species evolving according to a symmetric simple exclusion process. This mapping yields an analytic expression for the entanglement asymmetry and provides a simple microscopic mechanism for the quantum Mpemba effect: stronger initial symmetry breaking corresponds to a denser particle configuration, which enhances the frequency of particle encounters and thereby accelerates symmetry restoration.
