Excited-state Quantum Phase Transitions in the Anharmonic Lipkin-Meshkov-Glick Model: Dynamical Aspects
- Others:
- Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
- Universidad de Sevilla. Departamento de Física Aplicada III
- Ministerio de Ciencia e Innovación (MICIN). España
- European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER)
- Junta de Andalucía
- Ministerio de Economía y Competitividad (MINECO). España
Citation
Description
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, Phys. Rev. E 106, 044125 (2022)2470-004510.1103/PhysRevE.106.044125]. 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.
Abstract
Ministerio de Ciencia e Innovación PID2019-104002GB-C21, PID2019-104002GB-C22, PID2020-114687GB-I00
Abstract
European Commission. Fondo Europeo de Desarrollo Regional UHU-1262561, PY2000764, US-1380840
Abstract
Junta de Andalucía P20_01247
Abstract
Ministerio de Economía y Competitividad UNHU-15CE-2848
Additional details
- URL
- https://idus.us.es/handle//11441/153104
- URN
- urn:oai:idus.us.es:11441/153104
- Origin repository
- USE