Three-dimensional simulations of quantum transport in semiconductor nanostructures

Abstract

We introduce the planar supercell method as a means for treating three-dimensional quantum transport in mesoscopic tunnel structures. Our model treats potential variations along the growth direction as well as the lateral directions. The flexibility of the method allows us to examine a variety of physical phenomena relevant to quantum transport, including alloy disorder, interface roughness, defect impurities, and zero-dimensional, one-dimensional, and two-dimensional quantum confinement, in a variety of device geometries ranging from double barrier heterostructures to quantum wire electron waveguides. Using this method, we have studied the transport properties of double barrier heterostructures with alloy barriers, including the effect of clustering in the alloy layers. We have also examined interface roughness in double barrier structures, and analyzed k∥ scattering and lateral localization. In addition, we have studied the transport properties of a quantum wire electron waveguide, and explored its sensitivity to the geometry of waveguide openings.