CW OPERATION OF MONOLITHIC ARRAYS OF SURFACE-EMITTING FOLDED-CAVITY INGAAS ALGAAS DIODE-LASERS/

A monolithic 0.84-cm2 two-dimensional array of surface-emitting folded -cavity InGaAs/AlGaAs diode lasers was mounted junction up on a W/Cu m icrochannel heatsink and evaluated under CW operating conditions. Each laser in the array contained two upward-deflecting internal-cavity 45 -degrees mirrors, which were etched using chlorine ion-beam-assisted e tching, and two top-surface facets. The CW threshold current densities of different sections of the array were less-than-or-equal-to 223 A/c m2, while effective CW differential quantum efficiencies were greater- than-or-equal-to 30%. A CW output power of over 40 W was obtained from the entire array, while a current-limited output power density of 84 W/cm2 with an average temperature rise of approximately 30-degrees-C w as obtained from a quarter of the array.