PseudoSkyrmion Effects on Tunneling Conductivity in Coherent Bilayer Quantum Hall States at $\nu =1$

TL;DR

This paper proposes that pseudoSkyrmions explain the unexpectedly large but finite interlayer tunneling conductivity in coherent bilayer quantum Hall states at =1, accounting for dissipation and magnetic field effects.

Contribution

It introduces a new mechanism involving pseudoSkyrmions to explain finite tunneling conductivity in bilayer quantum Hall systems, contrasting previous expectations of dissipationless tunneling.

Findings

PseudoSkyrmions induce finite conductivity due to an intrinsic polarization field.

The peak conductivity persists under weak magnetic fields but diminishes rapidly beyond  \u2265 0.1 Tesla.

The mechanism explains the experimental observations of anomalously large yet finite tunneling conductance.

Abstract

We present a mechamism why interlayer tunneling conductivity in coherent bilayer quantum Hall states at $\nu=1$ is anomalously large, but finite in the recent experiment. According to the mechanism, pseudoSkyrmions causes the finite conductivity, although there exists an expectation that dissipationless tunneling current arises in the state. PseudoSkyrmions have an intrinsic polarization field perpendicular to the layers, which causes the dissipation. Using the mechanism we show that the large peak in the conductivity remains for weak parallel magnetic field, but decay rapidly after its strength is beyond a critical one, $\sim 0.1$ Tesla.