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Magnetotransport in the presence of a longitudinal barrier: multiple quantum interference of edge states

A. M. Kadigrobov·M. V. Fistul·K. B. Efetov
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Abstract

Transport in a two-dimensional electron gas subject to an external magnetic field is analyzed in the presence of a \textit{longitudinal barrier.} We show that \textit{quantum interference of the edge states} bound by the longitudinal barrier results in a drastic change of the electron motion: the degenerate discrete Landau levels are transformed into an alternating sequence of energy bands and energy gaps. These features of the electron spectrum should result in a high sensitivity of thermodynamic and transport properties of the 2D electron gas to external fields. In particular, we predict giant oscillations of the ballistic conductance and discuss nonlinear current-voltage characteristics, coherent Bloch oscillations and effects of impurities

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A. M. Kadigrobov, M. V. Fistul, K. B. Efetov. 2005-06-06. Magnetotransport in the presence of a longitudinal barrier: multiple quantum interference of edge states. https://doi.org/10.1103/physrevb.73.235313

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