Influence of heating of the active region in InGaAsP/InP injection lasers on their spectral characteristics

Spectral and spatial characteristics of the output of InGaAsP/InP separate- confinement double heterostructure laser are investigated. The measurements are performed in quasicontinuous and continuous pumping regimes at room te mperature. These lasers are shown to be spatially single-mode over the enti re working range of currents. The broadening of the longitudinal modes unde r quasicontinuous pumping is attributed to heating of the active region of the lasers. The pump pulse duration at which heating of the active region o f the lasers can be neglected is estimated. (C) 1999 American Institute of Physics. [S1063-7850(99)03204-8].