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

TL;DR

This paper explores the complex nonlinear dynamics and entanglement behavior of an atom in a non-uniform cavity, considering atomic motion, Stark shifts, and coupling regimes, revealing topological transitions and spin switching effects.

Contribution

It provides a comprehensive analysis of atom-cavity interactions including atomic motion, Stark shifts, and coupling regimes, highlighting new dynamical phenomena and entanglement variations.

Findings

Atomic motion causes topological transitions in the system.

Stark shift influences the entanglement between atom and field.

Spatial motion leads to spin switching in non-resonant cases.

Abstract

In this paper we study the dynamics in the general case for a Tavis Cummings atom in a non-uniform cavity. In addition to the dynamical Stark shift, the center-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 the spatial motion of the atom inside the cavity in the resonant case leads to a transition between topologically different solutions. This effect is manifested by a singularity in the inter-level transition spectrum. In the non-resonant case, the spatial motion of the atom leads to a switching of the spin orientation. In both effects, the key factor is the relation between the values of the Stark shift and the cavity field coupling constant. We also investigate the entanglement of an atom in the cavity with the radiation field. It is shown that the entanglement between the atom and the field, usually quantified in terms of purity, decreases with increasing the Stark shift.