论文标题
分析开放量子系统中传输的密度基质重新归一化组方法
Analysis of a density matrix renormalization group approach for transport in open quantum systems
论文作者
论文摘要
了解一维量子系统与多个储层的复杂性能对分析方法和仿真技术构成了挑战。幸运的是，最近在封闭系统研究中广泛使用了密度矩阵重新归一化组的工具，最近也已扩展到开放系统的处理。我们提出了基于最新矩阵乘积状态（MP）和张量网络方法的这种方法的实现，该方法可为各种参数组合产生准确的结果。与大多数使用时间进化来达到稳态的方法不同，我们专注于与时间无关的算法，并着重于以与标准密度矩阵重新归一化组（DMRG）算法完全相同的语言重新规定问题，该算法由M. C.Bañuls等人提出。在物理中。莱特牧师。 114，220601（2015）。因此，它可以很容易地导出到任何可用的DMRG平台。我们表明，该实施适用于研究一维系统中的热传输。作为一个案例研究，我们通过比较自旋电流和磁化谱与分析结果来重点关注XXZ量子自旋链，并基准我们的结果。然后，我们探索可以通过分析来计算的内容。我们的代码可在https://www.github.com/heitorc7/odmrg上免费获得。
Understanding the intricate properties of one-dimensional quantum systems coupled to multiple reservoirs poses a challenge to both analytical approaches and simulation techniques. Fortunately, density matrix renormalization group-based tools, which have been widely used in the study of closed systems, have also been recently extended to the treatment of open systems. We present an implementation of such method based on state-of-the-art matrix product state (MPS) and tensor network methods, that produces accurate results for a variety of combinations of parameters. Unlike most approaches, which use the time-evolution to reach the steady-state, we focus on an algorithm that is time-independent and focuses on recasting the problem in exactly the same language as the standard Density Matrix Renormalization Group (DMRG) algorithm, initially put forward by M. C. Bañuls et al. in Phys. Rev. Lett. 114, 220601 (2015). Hence, it can be readily exported to any of the available DMRG platforms. We show that this implementation is suited for studying thermal transport in one-dimensional systems. As a case study, we focus on the XXZ quantum spin chain and benchmark our results by comparing the spin current and magnetization profiles with analytical results. We then explore beyond what can be computed analytically. Our code is freely available on github at https://www.github.com/heitorc7/oDMRG.
