Comment on "Revisiting the phase transitions of the Dicke model"

In the work of Das and Sharma [Phys. Rev. A 105, 033716 (2022)] the phase transitions of the Dicke model are studied. Its main result is that, besides the well-known quantum phase transition, excited-state quantum phase transition, and thermal phase transition exhibited by the model, there exists an...

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Detalles Bibliográficos
Autores: Corps, Angel L., Relaño Pérez, Armando
Tipo de recurso: artículo
Fecha de publicación:2022
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/72944
Acceso en línea:https://hdl.handle.net/20.500.14352/72944
Access Level:acceso abierto
Palabra clave:536
Integral approximation
Momentum-space
Bound-states
Field
Termodinámica
2213 Termodinámica
Descripción
Sumario:In the work of Das and Sharma [Phys. Rev. A 105, 033716 (2022)] the phase transitions of the Dicke model are studied. Its main result is that, besides the well-known quantum phase transition, excited-state quantum phase transition, and thermal phase transition exhibited by the model, there exists an upper bound energy E* beyond which the model ceases to exhibit quantum chaotic behavior and the structure of the eigenfunctions changes. Based on this finding, a number of well-established results about the Dicke model are called into question. We argue that this result and all its consequences are spurious numerical effects resulting from an improper truncation of the infinite-dimensional Hilbert space necessary for numerical diagonalization.