FACET AND BULK HEATING OF GAAS ALGAAS HIGH-POWER LASER ARRAYS STUDIEDIN SPATIALLY-RESOLVED EMISSION AND MICRO-RAMAN EXPERIMENTS/

Temperature profiles in the bulk and at the front facet of a 20 emitte r GaAs/AlGaAs double-quantum-well laser array are studied by spatially resolved luminescence and micro-Raman spectroscopy. For optical outpu t powers of about 1 W, the facet temperature of the individual emitter s differs by up to 90 K. In contrast, the temperature distribution ins ide the resonator is highly uniform with temperature differences of le ss than 2 K. The facet temperature distribution correlates with the ne ar-field intensity pattern of the laser array. Reabsorption of laser e mission close to the facet and subsequent surface recombination of the photogenerated carriers represent the main heating mechanism. (C) 199 6 American Institute of Physics.