Abstract

The output of a single-mode 633 nm He-Ne laser with internal mirrors is usually linearly polarized in one of two orthogonal directions. When the laser frequency is locked by injected light with the polarization axis of 45° for the direction, a change in the polarization state occurs at the frequency and the selected polarization remains even after the injection light is removed.¹ This bistable behavior in polarization is based on intracavity anisotropies of loss and phase. We observed the dependence of the polarization switching on the angle of θ = 0°, 45° and 90° between one of the laser polarization and the linear-polarized injection light.

© 1995 IEEE