Mode dynamics in VCSELs with feedback

Abstract

We investigate the relationship between the linear polarization mode present in a vertical-cavity surface-emitting laser (VCSEL) that is subjected to external optical feedback with either a sawtooth or sinusoidal driving current. We describe the relation through correlation, mutual information and transfer entropy. Our simulations show that in the absence of feedback and with the use of a sinusoidal driving current at high values of either frequency or input current, a generally strong correlation, mutual information and transfer entropy among existing modes can be established.