2-DIMENSIONAL SURFACE-EMITTING LEAKY-WAVE COUPLED LASER ARRAYS

Leaky-wave coupling has been used for the first time to phase-lock surface-emitting antiguided arrays in a two-dimensional (2-D) configuration. Small differences between the length of separate array sections can be compensated for by phase shifts induced by carrier injection between the sections. Both four- and nine-array-section devices, arranged in diamond-shaped patterns, were phase-locked. Four-array-section devices provide far-field patterns with 35% fringe visibility to 0.2-W pulsed output power. Higher spatial coherence (45% fringe visibility) to 3.9-W pulsed output power is obtained from nine-array-section devices. The large improvement in coherent power of the nine-array-section devices compared with the four-array-section devices appears to be because the former are parallel coupled. The inherent single-spatial-mode stability of resonant optical waveguide (ROW) arrays to high drive levels above threshold allows the application of a coupled-mode formalism to 2-D arrays of ROW devices. The modeling indicates that resonant 16-array-section devices will produce 10 W of spatially coherent power.