Analysis of discontinuities in quantum waveguide structures

Abstract
We have used the modal expansion of the wave function in the discontinuity region based on the superposition principle together with a mode-matching technique to investigate the transmission characteristics of semiconductor quantum wire structures with discontinuities. Our calculations compare quite well with published results for the theoretical transmission coefficient and experimental conductance of a T-stub and split-gate geometry, respectively. We apply this technique to analyze the effect of right-angle bends in narrow quantum wires which show strong resonant behavior due to the presence of discontinuities in this geometry.