Bilayer quantum Hall system at $\nu_t = 1$: pseudospin models and in-plane magnetic field

TL;DR

This paper develops and unifies pseudomagnon models for bilayer quantum Hall systems at total filling factor one, analyzing the effects of in-plane magnetic fields and finite temperature, with predictions aligning with experimental data.

Contribution

It introduces a unifying framework for pseudomagnon models and derives a ground state energy equation considering in-plane magnetic fields and temperature effects.

Findings

Models agree with experimental results at low electron densities and strong in-plane fields.

Finite-temperature effects are minimal at experimentally relevant temperatures.

Derived ground state energy equation matches observed behaviors in BQHSs.

Abstract

We investigate two theoretical pseudomagnon-based models for a bilayer quantum Hall system (BQHS) at total filling factor $\nu_t = 1$. We find a unifying framework which elucidates the different approximations that are made. We also consider the effect of an in-plane magnetic field in BQHSs at $\nu_t = 1$, by deriving an equation for the ground state energy from the underlying microscopic physics. Although this equation is derived for small in-plane fields, its predictions agree with recent experimental findings at stronger in-plane fields, for low electron densities. We also take into account finite-temperature effects by means of a renormalisation group analysis, and find that they are small at the temperatures that were investigated experimentally.