Broad-area semiconductor lasers with spatially modulated reflectivity of the mirrors

Emission properties of broad-area semiconductor lasers with stripes etched on one of the laser mirrors, perpendicular to the p-n junction plane, are described. Spatial modulation of the mirror reflectivity induced lasing of individual, phase coupled filaments and significantly affected the shape of the laser output beam. The cross-section of the beam became almost circular and had an intensity distibution along its horizontal and vertical axes that could be approximated by a Gaussian function.