Population inversion in an optically pumped single quantum well.

Reports that an optically pumped intersubband laser generator is proposed in which the continuum states above an Al[sub 0.2]Ga[sub 0.8]As-GaAs-Al[sub 0.2]Ga[sub 0.8]As single quantum well with a width of L=17nm serve as the highest level in a four-level laser system. Flexibility in the choice of pumping source; Simplification of the device fabrication.