论文标题
通过自动驾驶和外部驾驶广泛子系统的预热量
Pre-thermalization via self-driving and external driving of extensive subsystems
论文作者
论文摘要
当仅量子脉冲或从基态驱动的广泛子系统时,我们研究了相互作用的多组分量子系统的非平衡状态。作为一个具体的示例,我们考虑了一个系统,其中两个XXZ旋转链耦合到横向场ISING(TFI)链,并且只有TFI链中的横向场是从最初有序状态开始的。使用密度矩阵重新归一化组(DMRG)模拟和各种纠缠熵诊断来研究该系统。在量子淬灭的情况下,当突然打开横向场成为最大的能量量表时,所得的内部动力学会导致持续的振荡磁化(“自动驱动”)和新兴的保护法,从而导致热稳态。将时间依赖的驱动器应用于TFI链(“外部驾驶”)后,足够快速的驱动会引起并带有有限磁化的热稳态,而慢速驱动器会产生高温无序状态。我们简要地讨论了具有量子隧穿原子的有机材料方案的实验实施。
We investigate the non-equilibrium states of an interacting multi-component quantum system when only an extensive subsystem is quantum-quenched or driven from the ground state. As a concrete example, we consider a system where two XXZ spin chains are coupled to a transverse field Ising (TFI) chain, and only the transverse field in the TFI chain is quantum-quenched or periodically driven in time, starting from an initially ordered state. This system is studied using density matrix renormalization group (DMRG) simulations and various entanglement entropy diagnostics. In the case of quantum quenching, when the transverse field is suddenly switched on to become the largest energy scale, the resulting internal dynamics leads to a pre-thermal steady state with persistent oscillating magnetization (`self-driving') and emergent conservation laws. Upon applying the time-dependent drive to the TFI chain (`external driving'), sufficiently fast drive gives rise to a pre-thermal steady state with finite magnetization, whereas a slow drive generates a high-temperature disordered state. We briefly discuss the experimental implementation of our protocol in organic materials with quantum-tunneling hydrogen atoms.