Linearly polarized bistable localized structure in medium-size vertical-cavity surface-emitting lasers

We show that a 40-μm-diameter vertical-cavity surface-emitting laser (VCSEL) is capable of supporting spatially localized structures with linear polarization, orthogonal to the principal polarization. The VCSEL is biased above the lasing threshold and emits a well-defined linear polarization (principal polarization). A holding beam with orthogonal polarization is injected into the cavity, and a localized structure is spontaneously switched on. The orthogonally polarized localized structure is shown to be bistable when the injection current is varied. Numerical results based on a rate equation model support the experimental findings.