OPTICAL STUDY OF STRAINED QUANTUM-WELL WIRES

We have investigated strain-induced lateral quantum confinement in a GaAs quantum well, as well as strain propagation along the material growth direction. The lateral confinement was generated by etching a grating pattern into a stressor of InGaAs which overlies a GaAs quantum well. For strain-induced quantum well wires formed by an In0.35Ga0.65As stressor, the excitation intensity- and temperature-dependent photoluminescence spectra show two well-resolved one-dimensional subband transitions whose splitting is 7.5+/-0.5 meV. We used luminescence data for multiple quantum wells, set at different distances beneath an In0.3Ga0.7As stressor, to confirm that the propagation depth of strain along the material growth direction is comparable to the width of wire stressors.