Josephson Effects in Double-Layer Quantum Hall States

TL;DR

This paper demonstrates that under certain assumptions, double-layer quantum Hall states can exhibit Josephson effects with unit charge tunneling due to coherent electron tunneling enabled by degeneracy in electron number difference.

Contribution

It introduces a general framework showing Josephson effects in double-layer quantum Hall states resulting from strong interlayer correlations.

Findings

Coherent tunneling of a single electron is possible between layers.

Josephson effects with unit charge tunneling are demonstrated.

Degeneracy in electron number difference enables tunneling phenomena.

Abstract

Under quite plausible assumptions on double-layer quantum Hall states with strong interlayer correlation, we show in general framwork that coherent tunneling of a single electron between two layers is possible. It yields Josephson effects with unit charge tunneling. The origin is that Halperin states in the quantum Hall states are highly degenerate in electron number difference between two layers in the absence of electrons tunneling.