Abstract

Large optical cavity (LOG) structures with 3000, 5000, and 8000 A thick waveguide layers were grown by the MOCVD technique. Both evanescently-coupled and diffraction coupled arrays with center to center element spacings of 4.5,6,7.5 and 9 microns were fabricated. The device geometry was of the ridge waveguide type, with Schottky barrier lateral confinement. Typical threshold currents ranged from 20 to 25 mA per stripe, and output powers as high as 2 watts per facet were obtained from 11 element devices with no facet coatings. The closely spaced 4.5 microns center to center arrays and the 6 micron center to center diffraction- coupled arrays were characterized by single lobe far-field emission patterns. As predicted theoretically, LOG arrays with a 8000 A thick waveguide region were found to operate in the first order transverse mode, while the arrays with 5000 and 3000 A thick waveguide regions operated in the lowest order transverse mode.

© 1986 Optical Society of America