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Experimental Studies of Scaling Behavior of a Quantum Hall System with a Tunable Landau Level Mixing

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 نشر من قبل Tao Tu
 تاريخ النشر 2008
  مجال البحث فيزياء
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Temperature dependence of the longitudinal and Hall resistance is studied in the regime of localization-delocalization transition. We carry out measurements of a scaling exponent $kappa$ in the Landau level mixing region at several filling factors. The localization exponent $gamma$ is extracted using an approach based on the variable range hopping theory. The values of $gamma$ and $kappa$ are found to be universal, independent of filling factor in our sample. We can conclude that although Landau level mixing can change the degeneracy of a quantum Hall state, the value of the scaling exponent remains the same for a given sample that contains a fixed disorder profile.

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