Abstract

In the preceding paper we have seen polarization-related bistability in an optical system without a cavity. The system is composed of a cell containing sodium vapor, a γ/8 plate, and a mirror. The incident light is linearly polarized and is timed on a wing of the D₁ line. The system has a positive feedback loop for the rotation of polarization through competitive optical pumping by σ± components of the reflected light. Above a threshold, symmetry breaking takes place: the polarization rotates either clockwise or counterclockwise, and the atomic spin polarization is produced spontaneously parallel or anti-parallel to the direction of incident beam. We note that the system can be described by a very simple equation

© 1988 Optical Society of America