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Ringlike structures in the density--magnetic-field $ρ_{xx}$ diagram of two-subband quantum Hall systems

Gerson J. Ferreira·Henrique J. P. Freire·J. Carlos Egues
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Abstract

Motivated by recent experiments [Zhang \textit{et al.}, Phys. Rev. Lett. \textbf{95}, 216801 (2005) and Ellenberger \textit{et al.}, cond-mat/0602271] reporting novel ringlike structures in the density--magnetic-field ($n_{2D}$\emph{--B}) diagrams of the longitudinal resistivity $ρ_{xx}$ of quantum wells with two subbands, we investigate theoretically here the magneto-transport properties of these quantum-Hall systems. We determine $ρ_{xx}$ via both the Hartree and the Kohn-Sham self-consistent schemes plus the Kubo formula. While the Hartree calculation yields diamond-shaped structures in the $n_{2D}$\emph{--B} diagram, the calculation including exchange and correlation effects (Kohn-Sham) more closely reproduces the ringlike structures in the experiments.

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Gerson J. Ferreira, Henrique J. P. Freire, J. Carlos Egues. 2007-01-15. Ringlike structures in the density--magnetic-field $ρ_{xx}$ diagram of two-subband quantum Hall systems. https://doi.org/10.1002/pssc.200672856

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