Cavity quantum electrodynamics of strongly correlated electron systems: A no-go theorem for photon condensation

Autor: Gian Marcello Andolina, Vittorio Giovannetti, Allan H. MacDonald, Marco Polini, Francesco M. D. Pellegrino
Přispěvatelé: Andolina, G. M., Pellegrino, F. M. D., Giovannetti, V., Macdonald, A. H., Polini, M.
Rok vydání: 2019
Předmět:
Zdroj: Physical Review B 100 (2019): 121109-1–121109-6. doi:10.1103/PhysRevB.100.121109
info:cnr-pdr/source/autori:Andolina G.M.; Pellegrino F.M.D.; Giovannetti V.; Macdonald A.H.; Polini M./titolo:Cavity quantum electrodynamics of strongly correlated electron systems: A no-go theorem for photon condensation/doi:10.1103%2FPhysRevB.100.121109/rivista:Physical Review B/anno:2019/pagina_da:121109-1/pagina_a:121109-6/intervallo_pagine:121109-1–121109-6/volume:100
ISSN: 2469-9969
2469-9950
DOI: 10.1103/physrevb.100.121109
Popis: In spite of decades of work it has remained unclear whether or not superradiant quantum phases, referred to here as photon condensates, can occur in equilibrium. In this Rapid Communication, we first show that when a nonrelativistic quantum many-body system is coupled to a cavity field, gauge invariance forbids photon condensation. We then present a microscopic theory of the cavity quantum electrodynamics of an extended Falicov-Kimball model, showing that, in agreement with the general theorem, its insulating ferroelectric and exciton condensate phases are not altered by the cavity and do not support photon condensation. In spite of decades of work it has remained unclear whether or not superradiant quantum phases, referred to here as photon condensates, can occur in equilibrium. In this Rapid Communication, we first show that when a nonrelativistic quantum many-body system is coupled to a cavity field, gauge invariance forbids photon condensation. We then present a microscopic theory of the cavity quantum electrodynamics of an extended Falicov-Kimball model, showing that, in agreement with the general theorem, its insulating ferroelectric and exciton condensate phases are not altered by the cavity and do not support photon condensation.
Databáze: OpenAIRE