Abstract:
The electron-transport and optical properties of heterostructures with a surface InGaAs/InAlAs quantum well in the cases of inverted $\delta$ doping with Si atoms (below the quantum well) and of standard $\delta$ doping (above the quantum well) are compared. It is shown that, in the case of inverted doping, the two-dimensional electron density in the quantum well is increased in comparison with the case of the standard arrangement of the doping layer at identical compositions and thicknesses of other heterostructure layers. The experimentally observed features of low-temperature electron transport (Shubnikov–de Haas oscillations, Hall effect) and the photoluminescence spectra of heterostructures are interpreted by simulating the band structure.