Signatures of broken symmetries in the excitations of a periodic 2DEG coupled to a cylindrical photon cavity
Journal
New Journal of Physics
Journal Volume
28
Journal Issue
4
Start Page
043502
ISSN
1367-2630
Date Issued
2026-04-01
Author(s)
Gudmundsson, Vidar
Mughnetsyan, Vram
Rauf Abdullah, Nzar
Tang, Chi-Shung
Kuan, Wen-Hsuan
Moldoveanu, Valeriu
Manolescu, Andrei
Abstract
In a two-dimensional electron gas in a periodic lateral superlattice subjected to an external homogeneous magnetic field and in a cylindrical far-infrared photon cavity we search for effects of broken symmetries: Static ones, stemming from the unit cell of the system, and the external magnetic field together with the dynamic ones caused by the vector potential of the cavity promoting magnetic types of transitions, and the chirality of the excitation pulse. The Coulomb interaction of the electrons is described within density functional theory, but the electron–photon interactions are handled by a configuration interaction formalism within each step of the density functional approach, both for the static and the dynamic system. In the dynamical calculations we observe weak chiral effects that change character as the strength of the electron–photon interaction and the external magnetic field are increased. From the analysis of the chiral effects we identify an important connection of the para- and diamagnetic electron–photon interactions that promotes the diamagnetic interaction in the present system when the interaction strength is increased. Furthermore, the asymmetric potential in the unit cell of the square array activates collective oscillation modes that are not present in the system when the unit cell has a higher symmetry.
Subjects
broken symmetry
electron–photon interactions
excitations
external magnetic field
photon cavity
two-dimensional electron gas
Publisher
IOP Publishing
Type
journal article