THERMAL-ANALYSIS OF CLOSELY-PACKED 2-DIMENSIONAL ETCHED-WELL SURFACE-EMITTING LASER ARRAYS

A self-consistent thermal-electrical model of etched-well surface-emit ting GaAs-AlGaAs lasers is applied to study thermal properties of two- dimensional (2-D) arrays, Temperature profiles across small- and moder ate-size arrays are generated, Thermal problems associated with integr ation of vertical-cavity surface-emitting lasers (VCSEL's) into closel y packed 2-D arrays are addressed, In particular, thermal crosstalk be tween elements of the array is investigated. The results indicate seve re thermal crosstalk, even at relatively low pumping currents, with st rong individual-element temperature-profile nonuniformities, The asymm etry of individual waveguides caused by skewed temperature distributio ns can be exploited for controlling supermode structure in phase-locke d arrays, Optimization of 2-D etched-well laser array designs is prese nted, aimed at maximizing the optical output power density from the ar ray, We find that the highest output power density is strongly increas ing for arrays of small-diameter emitters, and that the optimal center -to-center spacing between emitters is equal to similar to 2.5-3 times their diameter.