Ballistic electron transmission through interfaces

Abstract

We report on a new method for calculating ballistic electron transmission through epitaxial interfaces and its application to a silicon twist boundary. This method is based on constructing the electronic states of the infinite system from the generalized Bloch states for each layer in the structure; these states are matched together at the layer boundaries to construct the composite wave function. We find that the conduction-band electrons and the degenerate light and heavy holes within thermal energies of the band gap are strongly scattered by the twist boundary, but that the split-off holes in the same energy range are not. These results, which are unexpected from naive effective-mass considerations, can be simply understood in terms of flux patterns of the band-extrema wave functions on the interface-matching plane.