Reduction of InGaAs/GaAs laser facet temperatures by band gap shifted extended cavities

Reflectance modulation measurements have been used to determine facet temperatures of InGaAs/GaAs double quantum well (QW) graded-index separate-confinement heterostructure ridge-waveguide lasers possessing band gap tuned passive cavity sections. We find that the incorporation of transparent extended cavities, produced by ion-implantation enhanced QW intermixing, significantly decreases the laser facet temperatures. The reduced photoabsorption occurring at the facets, achieved by the QW intermixing process, should lead to increases in both the maximum optical power levels and device longevity prior to the onset of catastrophic failure.