CLEAVED CAVITY OPTICALLY PUMPED INGAN-GAN LASER GROWN ON SPINEL SUBSTRATES

We report an optically pumped multiple-quantum-well laser of InGaN-GaN grown on cubic, (111)-oriented spinel substrates. The laser cavity is formed by cleaving. Atomic force microscopy shows that the cleaved Ga N and spinel facets are of similar flatness. The onset of lasing is cl early demonstrated by the saturation of spontaneous emission, abrupt l ine narrowing, and the highly polarized light output. A lasing thresho ld power of 140 kW/cm(2) is measured in a 400-mu m-long cavity at 150 K. (C) 1996 American Institute of Physics.