Exciton waveguide and lasing in structures with superfine GaAs quantum wells and InAs submonolayer inclusions in an AlGaAs host

The optical properties of structures with InAs islands and narrow GaAs quan tum wells in an AlGaAs host have been investigated. The InAs islands were f ormed by depositing a layer of InAs with an effective thickness less than o ne monolayer. The effect of an exciton waveguide and the onset of lasing du e to optical pumping in the red spectral range are demonstrated in structur es without external optical confinement by layers with a lower refractive i ndex. (C) 1999 American Institute of Physics. [S1063-7826(99)02204-8].