Temperature Dependence of Threshold Current Density Jth and DifferentialEfficiency Nd of High-Power InGaAsP/GaAs (Lambda = 0.8 Microns) Lasers

摘要

An experimental and theoretical study on temperature dependence of the thresholdcurrent density Jth and differential efficiency Eta sub d for the InGaAsP/GaAS laser diodes emitting at lambda = 0.8 microns was performed. Threshold current density Jth increases and differential efficiency Eta sub d decreases as temperature is increased mainly because of thermal broadening of the gain spectrum. However, the measured temperature dependence of Jth and Eta sub d could not be explained when only this effect was considered. In this letter, the temperature dependence of momentum relaxation rate hit of carriers was investigated by performing the photoluminescence study. At high temperature, increase of the momentum relaxation rate hit leads to reduction of the gain and mobility and increase of the optical loss, causing higher Jth and lower Eta sub d as experimentally observed. The resulting theoretical model provides a good explanation for the mechanism of the increase of Jth and decrease of Eta sub d. (MM).