Electronic states and quantum Hall effect in GaSb-InAs-GaSb quantum wells

The electronic states of an InAs quantum well buried a few tens of nm below a GaSb surface are described, assuming Fermi-level pinning in the lower part of the gap at this surface. This model accounts satisfactorily for a variety of experimental observations such as the imbalance of electron and hole concentrations, the relatively high electron mobility, and the appearance of quantum-Hall plateaus. Additional cyclotron-resonance measurements are also consistent with the proposed electronic structure. © 1987 The American Physical Society.