Polarization switching dynamics of vertical-cavity surface-emitting laser subject to negative optoelectronic feedback

Using the extended spin-flip model, we theoretically investigate the polarization switching dynamics of a vertical-cavity surface-emitting laser subject to negative optoelectronic feedback. The results show that when the laser operates at two different the spin-flip rates, the feedback intensity and delay time have great influence on polarization switching dynamics. At a slow spin-flip rate, with the increase of feedback intensity, switching current increases linearly, that the X polarization mode is compressed is contrary to the reported results based on isotropic optical feedback. The reason may be due to the fact that the negative optoelectronic feedback improves the X polarization mode threshold; the effect of delay time will vary with feedback intensity. At a fast spin-flip rate, the effect of feedback strength is different from at a slow spin-flip rate, the switching point current undergoes a process in which the current increases first and then decreases gradually, the switching point current is more sensitively dependent on the feedback strength; while effect of the delay time is similar to that at a slow spin-flip rate. In addition, we find that the spontaneous emission noise has a great influence on polarization switching dynamics.