Disorder-assisted tunneling through a double-barrier resonant-tunneling structure

Abstract

Three-dimensional elastic scattering of tunneling electrons caused by interface roughness is studied in a double-barrier structure. A formalism is used that treats the barrier potential exactly and the disorder potential perturbatively. Expressions are obtained for the leading-order corrections to the transmission coefficient. It is discovered that the effect of this scattering is very sensitive to the position of the rough interface and that the scattering tends to reduce the peak-to-valley ratio. The formalism may be modified to include a magnetic field applied in the direction of current flow. The disorder then leads to inter-Landau-level scattering and thus to the formation of subsidiary peaks in the transmission coefficient.