Tensor network simulation of chains of non-Markovian open quantum systems
Tensor network simulation of chains of non-Markovian open quantum systems
复制标题
DOI：
10.1103/physrevresearch.5.033078
复制
发表时间：
2022-01
影响因子：
4.2
通讯作者：
Gerald E. Fux;D. Kilda;B. Lovett;Jonathan Keeling
中科院分区：
文献类型：
--
作者：
Gerald E. Fux;D. Kilda;B. Lovett;Jonathan Keeling
我们引入了一种通用数值方法来计算量子系统链的动力学和多时间相关性，其中每个系统都可以与结构化环境强耦合。该方法将一般（可能非马尔可夫）开放量子系统的过程张量形式与一维链的时间演化块抽取（TEBD）相结合。它系统地降低了源自系统环境相关性的数值复杂性，然后将其集成到完整的多体问题中，从而使广泛的应用在数值上变得可行。我们通过研究两个例子来说明这种方法的威力。首先，我们研究具有强耦合热引线的短 XYZ 海森堡链的各个自旋的热化。我们的结果证实了当与单个浴耦合时链条的完全热化，并且当链条放置在热浴和冷浴之间时揭示了低、中和高频状态下不同的有效温度。其次，我们研究了当每个位点耦合到其自己的浴时，较长 XY 链中的扩散动力学。
We introduce a general numerical method to compute dynamics and multi-time correlations of chains of quantum systems, where each system may couple strongly to a structured environment. The method combines the process tensor formalism for general (possibly non-Markovian) open quantum systems with time evolving block decimation (TEBD) for 1D chains. It systematically reduces the numerical complexity originating from system-environment correlations before integrating them into the full many-body problem, making a wide range of applications numerically feasible. We illustrate the power of this method by studying two examples. First, we study the thermalization of individual spins of a short XYZ Heisenberg chain with strongly coupled thermal leads. Our results confirm the complete thermalization of the chain when coupled to a single bath, and reveal distinct effective temperatures in low, mid, and high frequency regimes when the chain is placed between a hot and a cold bath. Second, we study the dynamics of diffusion in an longer XY chain, when each site couples to its own bath.