Modal dynamics above the threshold of higher-order transverse modes in a vertical-cavity surface-emitting laser with isotropic optical feedback

Abstract

We have experimentally studied modal dynamics of a vertical-cavity surface-emitting laser (VCSEL) above the threshold of higher-order transverse modes when the VCSEL is subject to isotropic optical feedback. The dynamics of the higher-order mode reveals resemblance to the so-called low-frequency fluctuation (LFF) and the transition from LFF to coherence collapse near the threshold of single-transverse-mode VCSEL. Influence of control parameters on the dynamics is investigated, and possible mechanism of the dynamics is discussed.