Semiclassical approach to the quantum Loschmidt echo in deep quantum regions: from validity to breakdown.
Semiclassical approach to the quantum Loschmidt echo in deep quantum regions: from validity to breakdown.
复制标题
DOI：
10.1103/physreve.86.066203
复制
发表时间：
2012-09
期刊：
影响因子：
--
通讯作者：
P. Qin;Qian Wang;Wen-ge Wang
中科院分区：
文献类型：
--
作者：
P. Qin;Qian Wang;Wen-ge Wang
半经典的结果通常被期望在半经典区域中是有效的。一个有趣的问题是，在可以引入适当的有效普朗克常数的模型中，当有效普朗克常数增加时，半经典预言在多大程度上仍然有效？在本文中，我们数值研究了这个问题，侧重于半经典预测的量子Loschirton回声在深量子区域的衰减。我们的数值模拟，在混沌制度中进行的ESTA模型和踢转子模型，也在横向场的一维伊辛链的临界区域，表明半经典预测可能工作，即使在深量子区，特别是在所谓的费米黄金法则制度的微扰强度。
Semiclassical results are usually expected to be valid in the semiclassical regime. An interesting question is, in models in which appropriate effective Planck constants can be introduced, to what extent will a semiclassical prediction stay valid when the effective Planck constant is increased? In this paper, we numerically study this problem, focusing on semiclassical predictions for the decay of the quantum Loschmidt echo in deep quantum regions. Our numerical simulations, carried out in the chaotic regime in the sawtooth model and in the kicked rotator model and also in the critical region of a one-dimensional Ising chain in transverse field, show that the semiclassical predictions may work even in deep quantum regions, particularly for perturbation strength in the so-called Fermi-Golden-Rule regime.