Switching between polarized modes of a vertical-cavity surface-emitting laser by isotropic optical feedback

Experiments are described that show that polarization of light in a vertical-cavity surface-emitting laser subjected to isotropic optical feedback can jump regularly back and forth between two orthogonal states when the injection current is increased. The polarization-resolved light-current characteristic curves are thus channeled. This effect occurs when the dichroism of the laser is weak enough to allow the effective (isotropic) reflectance to impose the polarization. A comparison of a model introduced by San Miguel [Phys. Rev. A52, 1728 (1995)] and the standard equations indicates that the best description is given when no spin relaxation is included.