Microstructure-based lasing in GaN/AlGaN separate confinement heterostructures

The authors report on an experimental study of microstructure-based lasing in an optically pumped GaN/AlGaN separate confinement heterostructure (SCH). They achieved low-threshold ultra-violet lasing in optically pumped GaN/AlGaN separate confinement heterostructures over a wide temperature range. The spacing, directionality, and far-field patterns of the lasing modes are shown to be the result of microcavities that were naturally formed in the structures due to strain relaxation. The temperature sensitivity of the lasing wavelength was found to be twice as low as that of bulk-like GaN films. Based on these results, the authors discuss possibilities for the development of ultra-violet laser diodes with increased temperature stability of the emission wavelength.