Long-wavelength emission in structures with quantum dots formed in the stimulated decomposition of a solid solution at strained islands

When an array of strained InAs nanoislands formed on a GaAs surface is over grown by a thin (1-10 nm) layer of an indium-containing solid solution, sti mulated decomposition of the solid solution is observed. This process cause s the formation of zones of elevated indium concentration in the vicinity o f the nanoislands. The volume of newly formed InAs quantum dots increases a s a result of this phenomenon, producing a substantial long-wavelength shif t of the photoluminescence line. This effect is enhanced by lowering the su bstrate temperature, and it depends weakly on the average width of the band gap of the solid solution. The indicated approach has been used successful ly in achieving room-temperature emission at a wavelength of 1.3 mu m. (C) 1999 American Institute of Physics. [S1063-7826(99)02208-5].