Spectral and dynamical validity of the rotating-wave approximation in the quantum and semiclassical Rabi models

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Coleman, H. F. A., Twyeffort, E. K.
Format: Preprint
Publié: 2024
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866929289441574912
author Coleman, H. F. A.
Twyeffort, E. K.
author_facet Coleman, H. F. A.
Twyeffort, E. K.
contents Ultrastrong coupling (USC) in the quantum Rabi model, characterized by the breakdown of the rotating-wave approximation (RWA) has become a topic of considerable interest and study. This critical reevaluation of the validity of the RWA concludes that the accepted definition of USC in terms of a fixed ratio of coupling to field frequency is inadequate. Connecting an improved spectral validity criterion with the derivation of the semiclassical limit predicts that the dynamical validity of the quantum RWA should be linked to that of the corresponding semiclassical model. This, however, is not supported by numerical calculations of coherent-state dynamics, which unambiguously demonstrate that spectral validity does not imply dynamical validity and reveal surprisingly complicated dependence on coupling and field amplitude.
format Preprint
id arxiv_https___arxiv_org_abs_2403_17628
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Spectral and dynamical validity of the rotating-wave approximation in the quantum and semiclassical Rabi models
Coleman, H. F. A.
Twyeffort, E. K.
Quantum Physics
Ultrastrong coupling (USC) in the quantum Rabi model, characterized by the breakdown of the rotating-wave approximation (RWA) has become a topic of considerable interest and study. This critical reevaluation of the validity of the RWA concludes that the accepted definition of USC in terms of a fixed ratio of coupling to field frequency is inadequate. Connecting an improved spectral validity criterion with the derivation of the semiclassical limit predicts that the dynamical validity of the quantum RWA should be linked to that of the corresponding semiclassical model. This, however, is not supported by numerical calculations of coherent-state dynamics, which unambiguously demonstrate that spectral validity does not imply dynamical validity and reveal surprisingly complicated dependence on coupling and field amplitude.
title Spectral and dynamical validity of the rotating-wave approximation in the quantum and semiclassical Rabi models
topic Quantum Physics
url https://arxiv.org/abs/2403.17628