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

TL;DR

This paper investigates how quantum interference of edge states in a 2D electron gas with a longitudinal barrier alters electron spectrum, leading to significant effects on transport properties and potential for high sensitivity to external fields.

Contribution

It introduces the concept of quantum interference of edge states caused by a longitudinal barrier, transforming Landau levels into energy bands and gaps, affecting transport properties.

Findings

Giant oscillations of ballistic conductance predicted

Transformation of Landau levels into energy bands and gaps

High sensitivity of transport properties to external fields

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