论文标题
孤立的量子多体系统的热化和纠缠的作用
Thermalization of isolated quantum many-body system and the role of entanglement
论文作者
论文摘要
自量子力学早期以来，孤立量子系统的热化一直是一个非平凡的问题。在通用孤立的量子系统中，预计非平衡动力学会导致热化，表明量子动力学的统计力学出现。但是，多体量子系统的哪些特征促进量子热化尚不清楚。最近的实验进步表明，纠缠可能充当热剂，而不是普遍，尤其是尤其是。在这里，我们从理论上表明，在一个孤立的多体量子系统中可观察到的热平均值，该系统具有大量自由度，从系统的纠缠能量特征状态出现。特别是，我们表明，在纠缠能量本征及其边际的期望值等同于可观察到的微型典型和规范平均值。
Thermalization of an isolated quantum system has been a nontrivial problem since the early days of quantum mechanics. In generic isolated quantum systems, nonequilibrium dynamics is expected to result in thermalization, indicating the emergence of statistical mechanics from quantum dynamics. However, what feature of a many-body quantum system facilitates quantum thermalization is still not well understood. Recent experimental advancements have shown that entanglement may act as a thermalizing agent, not universally but particularly. Here, we theoretically show that the thermal averages of an observable in an isolated many-body quantum system with a large number of degrees of freedom emerge from the entangled energy eigenstates of the system. In particular, we show that the expectation values of an observable in entangled energy eigenstates and its marginals are equivalent to the microcanonical and canonical averages of the observable.
