Prethermalization, thermalization, and Fermi's golden rule in quantum many-body systems
Prethermalization, thermalization, and Fermi's golden rule in quantum many-body systems
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DOI：
10.1103/physrevb.104.184302
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发表时间：
2021-09
影响因子：
3.7
通讯作者：
Krishnanand Mallayya;M. Rigol
中科院分区：
文献类型：
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作者：
Krishnanand Mallayya;M. Rigol
本文研究了弱扰动不可积系统中局部观测量的预热化和热化动力学，系统的哈密顿量形式为ω 0 + gV ω，其中ω 0是不可积的，gV ω是扰动。我们探讨远离平衡初始状态的热力学极限，使用数值关联的集群扩展（NLCE），并在有限的系统与周期性边界，使用精确对角化的动态。我们认为，一般的可观测量表现出一个两步松弛过程，一个快速的预热动力学，其次是一个缓慢的热化，只有当微扰打破了一个守恒量的0.00，如果在初始状态的守恒量的值是O（1）不同于热化后的。我们表明，缓慢的热化动力学的特点是由一个速率blog，这可以准确地确定使用费米黄金法则（FGR）方程。
We study the prethermalization and thermalization dynamics of local observables in weakly perturbed nonintegrable systems, with Hamiltonians of the form Ĥ0 + gV̂ , where Ĥ0 is nonintegrable and gV̂ is a perturbation. We explore the dynamics of far from equilibrium initial states in the thermodynamic limit using a numerical linked cluster expansion (NLCE), and in finite systems with periodic boundaries using exact diagonalization. We argue that generic observables exhibit a twostep relaxation process, with a fast prethermal dynamics followed by a slow thermalizing one, only if the perturbation breaks a conserved quantity of Ĥ0 and if the value of the conserved quantity in the initial state is O(1) different from the one after thermalization. We show that the slow thermalizing dynamics is characterized by a rate ∝ g, which can be accurately determined using a Fermi golden rule (FGR) equation.