Quantum relaxation and finite-size effects in the XY chain in a transverse field after global quenches
Quantum relaxation and finite-size effects in the XY chain in a transverse field after global quenches
复制标题
DOI：
10.1209/0295-5075/99/30004
复制
发表时间：
2012-08-01
期刊：
影响因子：
1.8
通讯作者：
Igloi, F.
中科院分区：
文献类型：
--
作者：
Blass, B.;Rieger, H.;Igloi, F.
我们考虑横向场中量子 XY 链的全局猝灭，并研究有限系统中磁化强度的非平衡弛豫和相关函数以及纠缠熵。对于有序相的淬火，半经典理论 (SCT) 可以根据弹道运动的准粒子对很好地描述确切的结果。对于有限系统，可以正确预测局部序参数和相关函数的动态演化的准周期行为，包括周期长度、指数松弛、准稳态状态和一个周期内的指数递推。在热力学极限下，SCT 对于纠缠熵而言是精确的，其修改版本遵循 Calabrese P. 等人的方法，J. Stat。机甲。 (2012) P07016，磁化强度和相关函数也是精确的。平稳相关函数由广义吉布斯系综描述。版权所有 (C) EPLA，2012
We consider global quenches in the quantum XY chain in a transverse field and study the nonequilibrium relaxation of the magnetization and the correlation function as well as the entanglement entropy in finite systems. For quenches in the ordered phase the exact results are well described by a semiclassical theory (SCT) in terms of ballistically moving quasi-particle pairs. For finite systems quasi-periodic behaviour of the dynamical evolution of the local order parameter and the correlation functions is predicted correctly including the period length, an exponential relaxation, a quasi-stationary regime and an exponential recurrence in one period. In the thermodynamic limit the SCT is exact for the entanglement entropy and its modified version following the method of Calabrese P. et al., J. Stat. Mech. (2012) P07016, is exact for the magnetization and the correlation function, too. The stationary correlation function is shown to be described by a generalized Gibbs ensemble. Copyright (C) EPLA, 2012