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Communications in Theoretical Physics

Study of Some Properties of Two-Level Atom in Quantum Optics

Rui‐Hua Xie, Gong-ou Xu, Dun-huan Liu

Published Apr 30, 1997• 6 citations

Abstract

With the concept of negative photon and the -photon J C model, we investigate analytically the effect of virtual photon field on the collapse revival effect of atomic inversion and squeezing of atom, we find that there is a significant effect of virtual photon field on atomic inversion and squeezing of atom; with the one-photon model as an example, we find that the squeezing of atom occurs periodically, the time and times of squeezing are only related to the resonance frequency and the amplitude of squeezing related to coupling constant of atom field, mean photon number and resonance frequency; also we show that the effect of squeezing of atom does not exist within rotating wave approximation if . Taking the approach of nearest-neighboring spectrum in the quantum chaos field, we investigate the properties of energy spectrum in one-photon JC model and show that the integrable region, non-integrable region and transition region of this system can be illustrated by a phase diagram;also we discuss the influence of interaction of atoms on spectrum and statistics of adjacent energy levels, we find that the influence of interaction is little obvious in strong field but takes great important role in weak field.

DOI: 10.1088/0253-6102/27/3/265

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