Weakened Topological Protection of the Quantum Hall Effect in a Cavity

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Rokaj, Vasil, Wang, Jie, Sous, John, Penz, Markus, Ruggenthaler, Michael, Rubio, Angel
Format: Preprint
Publié: 2023
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866911761391681536
author Rokaj, Vasil
Wang, Jie
Sous, John
Penz, Markus
Ruggenthaler, Michael
Rubio, Angel
author_facet Rokaj, Vasil
Wang, Jie
Sous, John
Penz, Markus
Ruggenthaler, Michael
Rubio, Angel
contents We study the quantum Hall effect in a two-dimensional homogeneous electron gas coupled to a quantum cavity field. As initially pointed out by Kohn, Galilean invariance for a homogeneous quantum Hall system implies that the electronic center of mass (CM) decouples from the electron-electron interaction, and the energy of the CM mode, also known as Kohn mode, is equal to the single particle cyclotron transition. In this work, we point out that strong light-matter hybridization between the Kohn mode and the cavity photons gives rise to collective hybrid modes between the Landau levels and the photons. We provide the exact solution for the collective Landau polaritons and we demonstrate the weakening of topological protection at zero temperature due to the existence of the lower polariton mode which is softer than the Kohn mode. This provides an intrinsic mechanism for the recently observed topological breakdown of the quantum Hall effect in a cavity [Appugliese et al., Science 375, 1030-1034 (2022)]. Importantly, our theory predicts the cavity suppression of the thermal activation gap in the quantum Hall transport. Our work paves the way for future developments in the cavity control of quantum materials.
format Preprint
id arxiv_https___arxiv_org_abs_2305_10558
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Weakened Topological Protection of the Quantum Hall Effect in a Cavity
Rokaj, Vasil
Wang, Jie
Sous, John
Penz, Markus
Ruggenthaler, Michael
Rubio, Angel
Mesoscale and Nanoscale Physics
We study the quantum Hall effect in a two-dimensional homogeneous electron gas coupled to a quantum cavity field. As initially pointed out by Kohn, Galilean invariance for a homogeneous quantum Hall system implies that the electronic center of mass (CM) decouples from the electron-electron interaction, and the energy of the CM mode, also known as Kohn mode, is equal to the single particle cyclotron transition. In this work, we point out that strong light-matter hybridization between the Kohn mode and the cavity photons gives rise to collective hybrid modes between the Landau levels and the photons. We provide the exact solution for the collective Landau polaritons and we demonstrate the weakening of topological protection at zero temperature due to the existence of the lower polariton mode which is softer than the Kohn mode. This provides an intrinsic mechanism for the recently observed topological breakdown of the quantum Hall effect in a cavity [Appugliese et al., Science 375, 1030-1034 (2022)]. Importantly, our theory predicts the cavity suppression of the thermal activation gap in the quantum Hall transport. Our work paves the way for future developments in the cavity control of quantum materials.
title Weakened Topological Protection of the Quantum Hall Effect in a Cavity
topic Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2305.10558