Minimal rate equations describing polarization switching in vertical-cavity surface-emitting lasers

Intensity rate equations for two nearly degenerate modes are derived for current driven polarization switching (PS) in vertical-cavity surface-emitting lasers (VCSELs). We show that the introduction of a current-dependent gain that saturates with increasing optical power leads to a minimal description of a PS experiment. The main advantage of these rate equations compared to more sophisticated model equations is the possibility to describe analytically the PS dynamical phenomenon. We obtain a simple expression for the switching time which agrees with experimental observations. (C) 2002 Published by Elsevier Science B.V.