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arXiv · 1008.0650

Fractional quantum Hall effects in bilayers in the presence of inter-layer tunneling and charge imbalance

Michael R. Peterson·Z. Papic·S. Das Sarma
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Abstract

Two-component fractional quantum Hall systems are providing a major motivation for a large section of the physics community. Here we study two-component fractional quantum Hall systems in the spin-polarized half-filled lowest Landau level (filling factor 1/2) and second Landau level (filling factor 5/2) with exact diagonalization utilizing both the spherical and torus geometries. The two distinct two-component systems we consider are the true bilayer and effective bilayers (wide-quantum-well). In each model (bilayer and wide-quantum-well) we completely take into account inter-layer tunneling and charge imbalancing terms. We find that in the half-filled lowest Landau level, the FQHE is described by the two-component Abelian Halperin 331 state which is remarkably robust to charge imbalancing. In the half-filled second Landau, we find that the FQHE is likely described by the non-Abelian Moore-Read Pfaffian state which is also quite robust to charge imbalancing. Furthermore, we suggest the possibility of experimentally tuning from an Abelian to non-Abelian FQHE state in the second Landau level, and comment on recent experimental studies of FQHE in wide quantum well structures.

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Michael R. Peterson, Z. Papic, S. Das Sarma. 2010-08-03. Fractional quantum Hall effects in bilayers in the presence of inter-layer tunneling and charge imbalance. https://doi.org/10.1103/physrevb.82.235312

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