REDUCTION OF THE THRESHOLD TEMPERATURE SENSITIVITY OF 1.55 MU-M INGAASP LASERS BY SUBNANOSECOND OPTICAL-EXCITATION

InGaAsP lasers operating at 1. 5 to 1. 6 mu m were pumped optically with a pulsed 1. 06 mu m source. The temperature dependence of the pump energy at laser threshold has been measured for temperatures from 170 to 330 K. Pump pulse widths of 300 ns and 150-300 ps were employed, long and short compared to the carrier life-time in the laser material. Over the high-temperature range of 260 to 330 K short pulse excitation gives a considerable reduction of the threshold temperature sensitivity with a characteristic temperature T//0 prime equals 85 K compared to T//0**h equals 45 K for long-pulse excitation. This is in qualitative agreement with previous results on electrically excited lasers although the temperature sensitivity of the optically excited lasers is larger.