Gauge-independent emission spectra and quantum correlations in the ultrastrong coupling regime of open system cavity-QED
Salmon Will,
Gustin Chris,
Settineri Alessio,
Di Stefano Omar,
Zueco David,
Savasta Salvatore,
Nori Franco,
Hughes Stephen
Affiliations
Salmon Will
Department of Physics, Engineering Physics and Astronomy, Queen’s University, KingstonON K7L 3N6, Canada
Gustin Chris
Department of Physics, Engineering Physics and Astronomy, Queen’s University, KingstonON K7L 3N6, Canada
Settineri Alessio
Dipartimento di Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della Terra, Università di Messina, MessinaI-98166, Italy
Di Stefano Omar
Dipartimento di Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della Terra, Università di Messina, MessinaI-98166, Italy
Zueco David
Instituto de Ciencia de Materiales de Aragón and Departamento de Física de la Materia Condensada, CSIC-Universidad de Zaragoza, Pedro Cerbuna 12, Zaragoza50009, Spain
Savasta Salvatore
Dipartimento di Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della Terra, Università di Messina, MessinaI-98166, Italy
Nori Franco
Theoretical Quantum Physics Laboratory, RIKEN Cluster for Pioneering Research, Wako-shi, Saitama351-0198, Japan
Hughes Stephen
Department of Physics, Engineering Physics and Astronomy, Queen’s University, KingstonON K7L 3N6, Canada
A quantum dipole interacting with an optical cavity is one of the key models in cavity quantum electrodynamics (cavity-QED). To treat this system theoretically, the typical approach is to truncate the dipole to two levels. However, it has been shown that in the ultrastrong-coupling regime, this truncation naively destroys gauge invariance. By truncating in a manner consistent with the gauge principle, we introduce master equations for open systems to compute gauge-invariant emission spectra, photon flux rates, and quantum correlation functions which show significant disagreement with previous results obtained using the standard quantum Rabi model. Explicit examples are shown using both the dipole gauge and the Coulomb gauge.
