@article{10272/20614,
year = {2021},
url = {http://hdl.handle.net/10272/20614},
abstract = {Using the Husimi quasiprobability distribution, we investigate the phase space signatures of excited-state quantum phase transitions (ESQPTs) in the Lipkin-Meshkov-Glick and coupled top models. We show that the ESQPT is evinced by the dynamics of the Husimi function, that exhibits a distinct time dependence in the different ESQPT phases. We also discuss how to identify the ESQPT signatures from the long-time averaged Husimi function and its associated marginal distributions. Moreover, from the calculated second moment and Wherl entropy of the long-time averaged Husimi function, we estimate the critical points of the ESQPT in both models, obtaining a good agreement with analytical (mean field) results. We provide a firm evidence that phase space methods are both a new probe for the detection and a valuable tool for the study of ESQPTs.},
publisher = {American Physical Society},
title = {Signatures of excited-state quantum phase transitions in quantum many-body systems: Phase space analysis},
doi = {10.1103/physreve.104.034119},
author = {Wang, Qian and Pérez Bernal, Francisco},
}