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arXiv · 0909.1729

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

O. Tieleman·A. Lazarides·D. Makogon·C. Morais Smith
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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.

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O. Tieleman, A. Lazarides, D. Makogon, C. Morais Smith. 2009-09-09. Bilayer quantum Hall system at $\nu_t = 1$: pseudospin models and in-plane magnetic field. https://doi.org/10.1103/physrevb.80.205315

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