arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2001.05289cond-mat.stat-mechcond-mat.str-elquant-ph
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典型性在量子多体系统实时动力学中的应用

Selected applications of typicality to real-time dynamics of quantum many-body systems

Tjark Heitmann, Jonas Richter, Dennis Schubert, Robin Steinigeweg

摘要:

广义地说,量子典型性的概念是指一个单一的纯态可以模拟完整的统计系综。这一事实引起了一个相当简单但非常有用的数值方法来模拟量子多体系统的动力学,称为动态量子典型性(DQT)。在本文中,我们给一个简短的概述DQT的选定应用程序,特别强调的是在低维晶格系统,如链或梯子的相互作用自旋或费米子的运输和热化的问题。对于这些系统,我们讨论了DQT提供了一种有效的手段来获得相对较大的希尔伯特空间维度和长时间尺度的依赖于时间的平衡关联函数,允许定量提取的传输系数的框架内,例如,线性响应理论此外,还讨论了DQT也可用于研究突然猝灭情形下的远离平衡态的动力学,其中初始态是猝灭前哈密顿量的热吉布斯态。最后,我们总结了一些DQT与其他方法,如数字连接簇展开或投影算子技术的组合。通过这种方式,我们展示了DQT的多功能性。

英文摘要:

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.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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