Observation and analysis of very rapid optical degradation of GaAs/GaAlAs DH laser material

We have observed and analyzed a very rapid form of degradation caused by the optical excitation of GaAs/GaAlAs DH laser material. It consists of the very rapid (50 μ/sec) development of 〈110〉-oriented lines originating at a mechanically damaged area and restricted to the optically excited area. TEM analysis shows that the degraded region consists of an orthogonal array of misfit dislocations of 60°type at the interface between the p-ternary layer and the active region. It seems likely that the dislocations are generated by glide as a result of the lattice misfit stress between GaAs and GaAlAs and that their energy of motion is supplied through nonradiative recombination events.