Two-level atom dynamics induced by a spin-orbit coupled optical vortex: dressed states formulation

Abstract

We consider here the interaction of a two-level atom with a tightly focused paraxial optical vortex beam in the dressed states formalism. The interaction is characterized by a term that couples the photon spin angular momentum (SAM) with its orbital angular momentum (OAM). This term affects all the physical quantities related to the dressed states, like their energies, populations, and relaxation rates among them. We also show that the Mollow triplet associated with the resonance fluorescence spectrum of a two-level atom acquires a chiral character. We give numerical examples based on experimentally accessible values of the various parameters, and we show that the chirality can give rise to observable modifications of the various physical quantities under consideration.