Abstract

An interesting feature of broad-area (BA) semiconductor lasers is their near-diffraction-limited fundamental mode in the lateral direction (parallel to the junction plane).^1,2 Unfortunately, the weak discrimination among the various lateral modes of BA lasers leads to broad far-field radiation patterns because the higher-order lateral modes are successively excited as the drive level is increased above the lasing threshold. In addition, the simultaneous oscillation of several lateral modes degrades the spatial coherence of the output beam.

© 1990 Optical Society of America