Resonant reflection at magnetic barriers in quantum wires

Hengyi Xu, T. Heinzel, M. Evaldsson, S. Ihnatsenka, I. V. Zozoulenko

Published 2007-01-05, updated 2007-03-20Version 2

The conductance of a quantum wire containing a single magnetic barrier is studied numerically by means of the recursive Greens function technique. For sufficiently strong and localized barriers, Fano - type reflection resonances are observed close to the pinch-off regime. They are attributed to a magnetoelectric vortex-type quasibound state inside the magnetic barrier that interferes with an extended mode outside. We furthermore show that disorder can substantially modify the residual conductance around the pinch-off regime.