Effect of linewidth enhancement factor on the generation of optical vortices in a class-A degenerate cavity semiconductor laser.

The dynamical behavior of a one-dimensional ring array of lasers generated in a class-A degenerate cavity semiconductor laser is numerically investigated. The class-A behavior of the laser is obtained by considering a low-loss vertical external cavity surface emitting laser (VECSEL), in which a telescope and a mask allow us to control the geometry and the linear nearest-neighbour coupling between the lasers. The behavior of the lasers is simulated using coupled rate equations, taking the influence of the Henry factor into account. It is shown that the ring array of lasers exhibits multistability. Moreover, by comparison with a class-B semiconductor laser, it is proved that the class-A nature of the laser makes it more robust to the increase of the Henry factor when it comes to generating topological charge carrying arrays of lasers, thus opening new perspectives of application for such lasers.