@article{10272/22981,
year = {2023},
url = {https://hdl.handle.net/10272/22981},
abstract = {The standard Lipkin-Meshkov-Glick (LMG) model undergoes a second-order ground-state quantum phase transition (QPT) and an excited-state quantum phase transition (ESQPT). The inclusion of an anharmonic term in the LMG Hamiltonian gives rise to a second ESQPT that alters the static properties of the model [Gamito et al., Phys. Rev. E 106, 044125 (2022)]. In the present work, the dynamical implications associated to this new ESQPT are analyzed. For that purpose, a quantum quench protocol is defined on the system Hamiltonian that takes an initial state, usually the ground state, into a complex excited state that evolves on time. The impact of the new ESQPT on the time evolution of the survival probability and the local density of states after the quantum quench,
as well as on the Loschmidt echoes and the microcanonical out-of-time-order correlator (OTOC) are discussed. The anharmonity-induced ESQPT, despite having a different physical origin, has dynamical consequences similar to those observed in the ESQPT already present in the standard LMG model.},
organization = {This work is part of the I+D+i Projects
No. PID2019-104002GB-C21, No. PID2019-104002GB-C22, and No. PID2020-114687GB-I00 funded by Grant No. MCIN/AEI/10.13039/501100011033. This work has also been partially supported by the Consejería de Conocimiento, Investigación y Universidad, Junta de Andalucía and European Regional Development Fund (ERDF), Refs. No.
UHU-1262561, No. PY2000764 (F.P.B.), and No. US-1380840, and it is also part of Grant Groups No. FQM-160 and No. FQM-287 and the Project PAIDI 2020 with Ref. No. P20_01247, funded by the Consejería de Economía, Conocimiento, Empresas y Universidad, Junta de Andalucía (Spain) and “ERDF-A Way of Making Europe,”
by the “European Union” or by the “European Union NextGenerationEU/PRTR.” Computing resources supporting this work were provided by the CEAFMC and Universidad de Huelva High Performance Computer (HPC@UHU) located in the Campus Universitario el Carmen and funded by FEDER/MINECO Project No. UNHU-15CE-2848.},
publisher = {American Physical Society},
title = {Excited-state quantum phase transitions in the anharmonic Lipkin-Meshkov-Glick model: Dynamical aspects},
doi = {10.1103/physreve.107.064134},
author = {Khalouf-Rivera, Jamil and Gamito, J. and Pérez Bernal, Francisco and Arias Carrasco, José Miguel and Pérez Fernández, Pedro},
}