1 Department of Photonics Engineering, Technical University of Denmark2 Diode Lasers and LED Systems, Department of Photonics Engineering, Technical University of Denmark3 Max-Born-Institut4 Ferdinand-Braun-Institut
The effect of external feedback on the degradation of 808 nm emitting AlGaAs-based high-power broad-area diode lasers is studied. For this purpose, early stages of gradual degradation are induced by accelerated aging at high power levels. While the quantum well that actually experiences the highest total optical load remains unaffected, severe impact by point defects is observed on the cladding layers and the waveguide. Extended defects such as dislocations, however, are not observed in such early stages of degradation, which are accompanied by gradual power loss of a few percent only.