Two-dimensional phase-locked arrays of vertical-cavity semiconductor lasers by mirror reflectivity modulation

Coupling of two-dimensional (2D) vertical-cavity surface-emitting lasers (VCSELs) to give a coherent supermode is described. The top metal layer of a stained-layer InGaAs quantum well VCSEL structure was patterned laterally by depositing various metals with different optical reflectivities. This lateral reflectivity patterning defined a 2D laser array sharing the same ‘‘supercavity’’. It is shown that these 2D arrays oscillate in a stable single, coherent 2D supermode. This was achieved with a simple planar process and without significant deterioration of threshold current and efficiency relative to an equivalent broad-area VCSEL.