Influence of optical feedback on the polarization switching of vertical-cavity surface-emitting lasers

We study theoretically the effect of isotropic and polarization-selective optical feedback on the polarization switching of vertical-cavity surface-emitting lasers. We use the framework of the spin-flip model that takes into account the spin degree of freedom of carriers in the semiconductor quantum well. We analyze the polarization switching dynamics for different values of the spin relaxation rate and find a good agreement with recent experimental results . We also study the influence of the external cavity length and find different dynamical behaviors for short and long external cavities.

I. Introduction

Vertical-cavity surface-emitting lasers (VCSELs) are attractive sources for high bit rate optical data transmission. The advantages of VCSELs over conventional, edge-emitting semiconductor lasers are single longitudinal mode operation, low threshold, high modulation efficiency, dense packing capability, and narrow circular beam profile [1].