Two-photon driven nonlinear dynamics and entanglement of an atom in a non uniform cavity

摘要

In this paper we study the dynamics in the general case for a Tavis Cummingsatom in a non-uniform cavity. In addition to the dynamical Stark shift, thecenter-of-mass motion of the atom and the recoil effect are considered in both- the weak and the strong cavity atom coupling regimes. It is shown that thespatial motion of the atom inside the cavity in the resonant case leads to atransition between topologically different solutions. This effect is manifestedby a singularity in the inter-level transition spectrum. In the non-resonantcase, the spatial motion of the atom leads to a switching of the spinorientation. In both effects, the key factor is the relation between the valuesof the Stark shift and the cavity field coupling constant. We also investigatethe entanglement of an atom in the cavity with the radiation field. It is shownthat the entanglement between the atom and the field, usually quantified interms of purity, decreases with increasing the Stark shift.