Polarization Mode-Hopping Suppression and Performance Enhancement by Optical Feedback in a Current-Driven Polarization Switching VCSEL

This research investigates the effect of optical feedback on the characteristics of current-driven polarization switching (CDPS) in a vertical-cavity surface-emitting laser (VCSEL). Experimental results indicate that the noise of polarization mode-hopping around the polarization switching current can be significantly suppressed by optical feedback. Furthermore, with the assistance of polarization-selective optical feedback, the percentage of successful switching of CDPS approaches to 100% at a driving frequency of up to 50 MHz. While, without optical feedback, that percentage is less than 26%. These results can be used to greatly enhance the performance of CDPS in VCSELs.