High temperature operation of AlGaInAs/InP lasers

We discuss the design of uncooled lasers which minimizes the change in both threshold current and slope efficiency over the temperature range from -40 to 85/spl deg/C. To prevent carrier overflow under high-temperature operation, the electron confinement energy is increased by using the Al/sub x/Ga/sub y/In/sub 1-x-y/As/InP material system instead of the conventional Ga/sub x/In/sub 1-x/As/sub y/P/sub 1-y//InP material system. Experimentally, the Al/sub x/Ga/sub y/In/sub 1-x-y/As/InP strained quantum well lasers show superior high temperature performances such as a small drop of 0.3 dB in slope efficiency when the heat sink temperature changes from 25 to 100/spl deg/C, a maximum CW operation temperature of 185/spl deg/C, a thermally-limited 3-dB bandwidth of 13.9 GHz at 85/spl deg/C, and a mean-time-to-failure of 33 years at 100/spl deg/C and 10 mW output power.