Optical feedback control of polarization switching in vertical-cavity surface-emitting lasers

In this paper we demonstrate experimentally and numerically that the polarization switching can be suppressed by the application of polarization-selective optical feedback. Vertical-cavity surface-emitting lasers (VCSELs) are attractive light sources in optical communication systems. Near threshold VCSELs usually emit in a dominant linearly polarized mode with a 15-30 dB suppressed orthogonally-polarized mode. When the injection current is increased in many devices it is observed that the polarization switches to the orthogonal state. Such polarization-switching impacts applications in polarization-sensitive systems.