Temperature Distributions in the GaAs-AlGaAs Double-Heterostructure Laser below and above the Threshold Current

Abstract

The temperature distribution in the double-heterostructure laser under cw operation was observed directly. The temperature distribution above the threshold differs from that below the threshold; that is, the narrowing of the distribution around the active region was observed above the threshold. This means that the heat source is concentrated at the active region when the diode lases. The dependence of the temperature rise on the differential quantum efficiency was also observed. These results can be understood qualitatively by assuming a change in thespatial distribution of the heat source in the double-heterostructure laser below and above the threshold.