Two-subband electron transport in nonideal quantum wells

Electron transport in nonideal quantum wells (QW’s) with large-scale variations of energy levels is studied when two subbands are occupied. Although the mean variations of these two levels are screened by the in-plane redistribution of electrons, the energies of both levels remain nonuniform over the plane. The effect of random inhomogeneities on the classical transport is studied within the framework of a local response approach for weak disorder. Both short-range and small-angle scattering mechanisms are considered. Magnetotransport characteristics and the modulation of the effective conductivity by transverse voltage are evaluated for different kinds of confinement potentials (hard-wall QW, parabolic QW, and stepped QW).