H01S 5/34393

Structure or shape of the active region; Materials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well lasers [SQW-lasers], multiple quantum well lasers [MQW-lasers] or graded index separate confinement heterostructure lasers [GRINSCH-lasers] in AIIIBV compounds, e.g. AlGaAs-laser {, InP-based laser characterised by the materials of the barrier layers not only based on AIIIBV compounds}