标题： 量子伊辛模型中淬火动力学临界性的精确结果 显示英文标题

标题： Exact results for the criticality of quench dynamics in quantum Ising models

摘要： 基于获得的精确结果，我们系统地研究了一维自旋-1/2横场伊辛模型在零温及有限温度初始状态下的淬火动力学。 我们关注外部场突然变化后系统的磁化以及相干时间演化过程。 对于零温初始状态，淬火磁化率作为初始场强的函数表现出与静态磁化率相似的强烈标度行为，而淬火磁化率作为最终场强的函数在量子临界点表现出不连续性。 即使对于有限温度初始系统的情况，这种不连续性依然稳健，并始终出现在量子临界点，这表明利用淬火动力学研究量子相变具有显著优势。 显示英文摘要

摘要： Based on the obtained exact results we systematically study the quench dynamics of a one-dimensional spin-1/2 transverse field Ising model with zero- and finite-temperature initial states. We focus on the magnetization of the system after a sudden change of the external field and a coherent time-evolution process. With a zero-temperature initial state, the quench magnetic susceptibility as a function of the initial field strength exhibits strongly similar scaling behaviors to those of the static magnetic susceptibility, and the quench magnetic susceptibility as a function of the final field strength shows a discontinuity at the quantum critical point. This discontinuity remains robust and always occurs at the quantum critical point even for the case of finite-temperature initial systems, which indicates a great advantage of employing quench dynamics to study quantum phase transitions.