FACET HEATING AND AXIAL TEMPERATURE PROFILES IN HIGH-POWER GAALAS GAAS LASER-DIODES/

Degradation of the facets represents a major reason reducing the perfo rmance and the lifetime of high-power laser diodes. Nonradiative surfa ce recombination of electrons and holes results in a strong heating of the facet region and subsequent defect accumulation. We theoretically investigated facet heating of an asymmetrically coated 20-stripe GaAs /GaAlAs laser diode array by a self-consistent calculation of the axia l profiles of temperature, carrier density, and optical intensity. To validate the model, we measured the facet temperature as a function of injection current using micro-Raman spectroscopy. Our results point t o the possibility of catastrophical optical damage at the reflection-c oated facet arising from the asymmetric thermal load of the facets. (C ) 1998 Elsevier Science Ltd. All rights reserved.