SPATIAL SEPARATION OF POLARIZATION COMPONENTS BY NONLINEAR BEAM RESHAPING IN A J=1 TO J=0 MEDIUM

Abstract

The diffractive reshaping that circularly polarized light beams undergo when coupled in a medium of homogenously broadened J=1→J=0 atoms is shown to be sensitively dependent on applied magnetic fields. In zero field, an elliptically polarized beam will retain its polarization everywhere in space, but a small longitudinal magnetic field can cause the beam to break up into spatially distinct regions of pure circular polarization. The beam behavior can be understood in terms of an encoding/diffraction sequence. An analytic solution for the atomic response function reveals the important roles played by transverse and longitudinal optical pumping.