Screening Effect and Quantum Transport in a Silicon Inversion Layer in Strong Magnetic Fields

Abstract

The broadening of Landau levels and the transport quantities, such as the transverse and Hall conductivity and cyclotron resonance linewidth, are calculated in an inversion layer on the (100) surface of p -type Si at zero temperature. Main scattering mechanisms are assumed to be charged impurity scattering and surface roughness scattering. A new expression for the surface roughness scattering is obtained. The self-consistent Born approximation is employed for the effect of scattering, and the random phase approximation for the screening. Because of the singular density of states the screening depends on the position of the Fermi level and becomes weak when it lies at the tail region of each Landau level. Scattering potentials become strong and of slowly varying type in this case. Except such a special case, overall features agree with the results obtained for short-ranged scatterers.