Diamagnetic shift inInxGa1−xAs/GaAs strained quantum wells

Abstract

Photoluminescence measurements were performed at liquid-helium temperatures at magnetic fields of up to 40 T for ${\mathrm{In}}_{\mathit{x}}$ ${\mathrm{Ga}}_{1\mathrm{-}\mathit{x}}$As/GaAs strained quantum wells confined within GaAs layers. The diamagnetic shift was obtained for the samples with different well widths and barrier heights under magnetic fields applied perpendicular and parallel to the well planes. The shift was observed to depend on the well width and barrier height under both configurations of the magnetic field. A model calculation was carried out in a framework of the variational method. The diamagnetic shift was therefore studied as functions of the well width, barrier height, and the magnetic-field configuration experimentally and theoretically; it is found to be a sensitive means to characterize the exciton’s dimensionality. Moreover, an additional confinement by the parallel field was identified with the observation of the emission intensity in the parallel-field configuration.