RT Journal Article T1 Entropy, chaos, and excited-state quantum phase transitions in the Dicke model A1 Lóbez, C. M. A1 Relaño Pérez, Armando AB We study nonequilibrium processes in an isolated quantum system-the Dicke model-focusing on the role played by the transition from integrability to chaos and the presence of excited-state quantum phase transitions. We show that both diagonal and entanglement entropies are abruptly increased by the onset of chaos. Also, this increase ends in both cases just after the system crosses the critical energy of the excited-state quantum phase transition. The link between entropy production, the development of chaos, and the excited-state quantum phase transition is more clear for the entanglement entropy. PB American Physical Society SN 2470-0045 YR 2016 FD 2016-07-26 LK https://hdl.handle.net/20.500.14352/18990 UL https://hdl.handle.net/20.500.14352/18990 LA eng NO ©2016 American Physical Society. This work has been partially supported by the Spanish Grants No. FIS2012-35316 and No. FIS2015-63770-P (MINECO/FEDER). C.M.L. is supported by the Spanish MECD Program "Becas de Colaboración." A.R. thanks R. Puebla for enlightening discussions. C.M.L. thanks A. Alsina and D. Méndez González for useful advice that clarified the meaning of several topics. NO Ministerio de Economía y Competitividad (MINECO)/FEDER NO Ministerio de Educación, Cultura y Deporte (MECD) DS Docta Complutense RD 18 abr 2025