Exploring many-body localization and thermalization using semiclassical methods
Exploring many-body localization and thermalization using semiclassical methods
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DOI：
10.1103/physreva.96.033604
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发表时间：
2017-09-05
影响因子：
2.9
通讯作者：
Rey, A. M.
中科院分区：
文献类型：
--
作者：
Acevedo, O. L.;Safavi-Naini, A.;Rey, A. M.
离散截断维格纳近似(DTWA)是一种用于探索多体量子动力学的半经典相空间方法。在这项工作中，我们研究了多体局部化(MBL)和热化使用DTWA，并将其性能与精确的数值解进行了比较。以具有短程相互作用的一维随机场Heisenberg自旋链为基准，通过与数值精确方法的比较，我们表明DTWA能够重现表征热相和MBL相的动力学特征。它在每个相中的较短时间内表现出最好的定量一致性，并且在相变附近表现出较大的失配。DTWA捕捉到了纠缠在MBL相中的对数增长，尽管纯经典平均场分析根本不会导致任何动力学。我们的结果表明，DTWA可以成为一种有用的方法来研究实验相关环境中的MBL和热化，这些环境是用精确的数值技术解决的，例如具有长程相互作用的系统和/或更高维度的系统。
The discrete truncated Wigner approximation (DTWA) is a semiclassical phase-space method useful for the exploration of many-body quantum dynamics. In this work we investigate many-body localization (MBL) and thermalization using DTWA and compare its performance to exact numerical solutions. By taking as a benchmark case a one-dimensional random field Heisenberg spin chain with short-range interactions, and by comparing to numerically exact techniques, we show that DTWA is able to reproduce dynamical signatures that characterize both the thermal and the MBL phases. It exhibits the best quantitative agreement at short times deep in each of the phases and larger mismatches close to the phase transition. The DTWA captures the logarithmic growth of entanglement in the MBL phase, even though a pure classical mean-field analysis would lead to no dynamics at all. Our results suggest the DTWA can become a useful method to investigate MBL and thermalization in experimentally relevant settings intractable with exact numerical techniques, such as systems with long-range interactions and/or systems in higher dimensions.