Experimental analysis of self-pulsation in 650-nm-wavelength AlGaInP laser diodes with epitaxial absorbing layers

We have produced self-pulsating 650-nm-wavelength AlGaInP lasers by the inclusion of saturable absorbing quantum wells (QW's) within the p-doped cladding layer. To maintain the pulsation characteristics at high temperature, a multiple QW design has been used. This reduces the saturation of the absorbing layers due to thermally activated charge leakage from the active region of the laser, thus enabling strong self-pulsation up to a maximum temperature of 100°C. The dynamic characteristics of the absorber wells have been measured using time-resolved photoluminescence techniques on the laser structures. The results indicate that the carrier lifetime in the absorber is determined by nonradiative processes with a typical decay time of 0.3 ns.