Interlayer Transport in Bilayer Quantum Hall Systems

TL;DR

This paper develops a theoretical framework for inter-layer transport in bilayer quantum Hall systems, explaining observed conductance phenomena and drawing parallels with Josephson junctions and spin-transfer devices.

Contribution

It introduces a novel theory that elucidates the inter-layer transport mechanisms and explains experimental conductance features in quantum Hall bilayers.

Findings

Explains the finite low bias interlayer conductance.

Describes the voltage width of the collective transport anomaly.

Highlights similarities and differences with Josephson junctions.

Abstract

Bilayer quantum Hall systems have a broken symmetry ground state at filling factor $\nu=1$ which can be viewed either as an excitonic superfluid or as a pseudospin ferromagnet. We present a theory of inter-layer transport in quantum Hall bilayers that highlights remarkable similarities and critical differences between transport in Josephson junction and ferromagnetic metal spin-transfer devices. Our theory is able to explain the size of the large but finite low bias interlayer conductance and the voltage width of this collective transport anomaly.