Evanescent Wave Spectroscopy of Sublevel Resonances near a Glass/Vapor Interface

Abstract

We report the observation of atomic sublevel coherence from a quasi-twodimensional region of atomic Na vapor near a glass surface. The ground state coherences are excited with a circularly polarized laser beam and detected with a linearly polarized probe beam that is incident on the interface under conditions of total interval reflection. The coherences of the atoms that are within the evanescent wave lead to selective absorption and phase shifts of the reflected beam which can be measured by a polarization-selective detection.