Exploring dynamical phase transitions and prethermalization with quantum noise of excitations
Exploring dynamical phase transitions and prethermalization with quantum noise of excitations
复制标题
DOI：
10.1103/physrevb.91.205136
复制
发表时间：
2014-09
影响因子：
3.7
通讯作者：
Pietro Smacchia;M. Knap;E. Demler;Alessandro Silva
中科院分区：
文献类型：
--
作者：
Pietro Smacchia;M. Knap;E. Demler;Alessandro Silva
（2014年9月5日收稿；2015年5月4日收稿；2015年5月26日发表）动态相变可以发生在孤立的量子系统中，这些系统是由突然的参数变化引起的。我们讨论了基于产生的激发态统计的动态相变的表征。我们考虑了大N极限下的O(N)模型和具有远程相互作用的自旋模型，并表明它们的预热稳态的动力学临界性最显著地体现在它们的高矩而不是平均激发数上。我们认为，无论模型的精确细节如何，缺陷波动的增长都带有动态临界性的独特特征。我们的理论结果应该与光学晶格中超冷玻色子原子的量子猝灭实验有关。
(Received 5 September 2014; revised manuscript received 4 May 2015; published 26 May 2015) Dynamical phase transitions can occur in isolated quantum systems that are brought out of equilibrium by sudden parameter changes. We discuss the characterization of such dynamical phase transitions based on the statistics of produced excitations. We consider both the O(N) model in the large-N limit and a spin model with long-range interactions and show that the dynamical criticality of their prethermal steady states manifests most dramatically not in the average number of excitations but in their higher moments. We argue that the growth of defect fluctuations carries unique signatures of the dynamical criticality, irrespective of the precise details of the model. Our theoretical results should be relevant to quantum quench experiments with ultracold bosonic atoms in optical lattices.