Near-infrared GaAsBi quantum well laser diodes (Conference Presentation)

Dilute bismide is a novel class of III-V semiconductor compound possessing a number of attractive physical properties such as a large band-gap bowing effect, a large spin-orbit split band and a less temperature sensitive band-gap etc. In this talk, I will present electrically pumped near infrared GaAsBi quantum well (QW) laser diodes (LDs) grown by molecular beam epitaxy with room-temperature lasing up to 1.14 m. Epitaxial growth is carefully optimized to ensure high bismuth incorporation and high optical quality at the same time. The LDs reveal an output power over 120 mW under pulsed excitation at 300 K and can operate under CW excitation up to 273 K. They also show high performance with an internal quantum efficiency of 86% and an internal optical loss of 10 cm-1. The characteristic temperature is 79 K in the temperature range of 225-350 K and the temperature coefficient of the lasing wavelength is 0.26 nm/K at 77-350 K, much smaller than 0.35-0.40 nm/K for InGaAs and InGaAsP QW LDs. These results suggest that GaAsBi LDs are attractive candidates for uncooled near infrared lasers on GaAs.