Numerical analysis of Dicke’s model for one atom

Abstract

Using the Green function technique, the authors calculate the transition probability amplitude for one atom interacting with a one-mode electromagnetic field, without assuming the rotating-wave approximation (RWA). The effects of the RWA are studied in the time and frequency domains. In the time domain, the periodicity of the typical RWA results is broken; in the frequency domain, the Bloch-Siegert shift is obtained