论文标题
典型性到量子多体系统的实时动力学的选定应用
Selected applications of typicality to real-time dynamics of quantum many-body systems
论文作者
论文摘要
宽松地说,量子典型性的概念是指单个纯状态可以模仿完整统计合奏的事实。这一事实引起了一种相当简单但非常有用的数值方法,以模拟量子多体系统的动力学,称为动力学量子典型性(DQT)。在本文中,我们简要概述了DQT的选定应用,其中特别强调了在低维晶格系统(如链条或相互作用的旋转或费米子的梯子)中有关运输和热化的问题。对于这些系统,我们讨论了DQT提供了一种有效的手段,以获得相对较大的希尔伯特空间维度和长时间尺度的时间依赖性平衡相关函数,从而可以在线性响应理论的框架内定量提取传输系数的定量提取。此外,讨论了DQT还可以用于研究突然淬火场景引起的远程平衡动力学,其中初始状态是液态前汉密尔顿的热吉布斯状态。最终,我们总结了DQT的一些组合以及其他方法,例如数值链接的群集扩展或投影操作员技术。这样,我们演示了DQT的多功能性。
Loosely speaking, the concept of quantum typicality refers to the fact that a single pure state can imitate the full statistical ensemble. This fact has given rise to a rather simple but remarkably useful numerical approach to simulate the dynamics of quantum many-body systems, called dynamical quantum typicality (DQT). In this paper, we give a brief overview of selected applications of DQT, where particular emphasis is given to questions on transport and thermalization in low-dimensional lattice systems like chains or ladders of interacting spins or fermions. For these systems, we discuss that DQT provides an efficient means to obtain time-dependent equilibrium correlation functions for comparatively large Hilbert-space dimensions and long time scales, allowing the quantitative extraction of transport coefficients within the framework of, e.g., linear response theory. Furthermore, it is discussed that DQT can also be used to study the far-from-equilibrium dynamics resulting from sudden quench scenarios, where the initial state is a thermal Gibbs state of the pre-quench Hamiltonian. Eventually, we summarize a few combinations of DQT with other approaches such as numerical linked cluster expansions or projection operator techniques. In this way, we demonstrate the versatility of DQT.