The quantum Rabi model for two qubits

We study a system composed of two nonidentical qubits coupled to a single mode quantum field. We calculate the spectra of the system in the deepstrong-coupling regime via perturbation theory up to second order corrections, and show that it converges to two forced oscillator chains for cases well int...

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Detalles Bibliográficos
Autor: BLAS MANUEL RODRIGUEZ LARA
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2013
País:México
Institución:Instituto Nacional de Astrofísica, Óptica y Electrónica
Repositorio:Repositorio Institucional del INAOE
Idioma:inglés
OAI Identifier:oai:inaoe.repositorioinstitucional.mx:1009/2199
Acceso en línea:http://inaoe.repositorioinstitucional.mx/jspui/handle/1009/2199
Access Level:acceso abierto
Palabra clave:info:eu-repo/classification/Inspec/Qubits
info:eu-repo/classification/Inspec/Quantum field
info:eu-repo/classification/Inspec/Hilbert space
info:eu-repo/classification/cti/1
info:eu-repo/classification/cti/22
info:eu-repo/classification/cti/2209
Descripción
Sumario:We study a system composed of two nonidentical qubits coupled to a single mode quantum field. We calculate the spectra of the system in the deepstrong-coupling regime via perturbation theory up to second order corrections, and show that it converges to two forced oscillator chains for cases well into that regime. Our predictions are confirmed by numerical calculation of the spectra using a parity decomposition of the corresponding Hilbert space. The numerical results point to two interesting behaviors in the ultra-strong-coupling regime: the rotating wave approximation is valid for some particular cases and there exist crossings in the spectra within each parity subspace. We also present the normal modes of the system and give an example of the time evolution of the mean photon number, population inversion, von Neuman entropy and Wootters concurrence in the ultra-strong- and deep-strongcoupling regimes.