Pronounced metal–insulator transition according to dipole trap model for two-dimensional Si-MOS structures

Abstract

Originally the dipole trap scattering model was treated with several approximations and limitations in order to obtain an analytical solution for the temperature and density dependence of the resistivity of high-mobility Si-MOS structures. In contrast, we perform numerical calculations within this model and are thus able to drop several of the earlier restrictions. We include the charge of the trap states in the effective potential run between the metallic gate and the two-dimensional electron layer. In addition, a spatial distribution of the trap density and an energetic broadening of the trap states is taken into account in our calculations. We are thus able to get a distinct metal-to-insulator transition within the dipole trap model for realistic assumptions.