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Coherent electronic transport in a multimode quantum channel with Gaussian-type scatterers

Jens Hjorleifur Bardarson·Ingibjorg Magnusdottir·Gudny Gudmundsdottir·Chi-Shung Tang·Andrei Manolescu·Vidar Gudmundsson
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Abstract

Coherent electron transport through a quantum channel in the presence of a general extended scattering potential is investigated using a T-matrix Lippmann-Schwinger approach. The formalism is applied to a quantum wire with Gaussian type scattering potentials, which can be used to model a single impurity, a quantum dot or more complicated structures in the wire. The well known dips in the conductance in the presence of attractive impurities is reproduced. A resonant transmission peak in the conductance is seen as the energy of the incident electron coincides with an energy level in the quantum dot. The conductance through a quantum wire in the presence of an asymmetric potential are also shown. In the case of a narrow potential parallel to the wire we find that two dips appear in the same subband which we ascribe to two quasi bound states originating from the next evanescent mode.

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Jens Hjorleifur Bardarson, Ingibjorg Magnusdottir, Gudny Gudmundsdottir, Chi-Shung Tang, Andrei Manolescu, Vidar Gudmundsson. 2004-08-19. Coherent electronic transport in a multimode quantum channel with Gaussian-type scatterers. https://doi.org/10.1103/physrevb.70.245308

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