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On transport in quantum Hall systems with constrictions

Siddhartha Lal
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Abstract

Motivated by recent experimental findings, we study transport in a simple phenomenological model of a quantum Hall edge system with a gate-voltage controlled constriction lowering the local filling factor. The current backscattered from the constriction is seen to arise from the matching of the properties of the edge-current excitations in the constriction ($ν_{2}$) and bulk ($ν_{1}$) regions. We develop a hydrodynamic theory for bosonic edge modes inspired by this model, finding that a competition between two tunneling process, related by a quasiparticle-quasihole symmetry, determines the fate of the low-bias transmission conductance. In this way, we find satisfactory explanations for many recent puzzling experimental results.

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Siddhartha Lal. 2006-11-08. On transport in quantum Hall systems with constrictions. https://doi.org/10.1209/0295-5075%2F80%2F17003

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