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Landau Level Mixing and Levitation of Extended States in Two Dimensions

F. D. M. Haldane·Kun Yang
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Abstract

We study the effects of mixing of different Landau levels on the energies of one-body states, in the presence of a strong uniform magnetic field and a random potential in two dimensions. We use a perturbative approach and develop a systematic expansion in both the strength and smoothness of the random potential. We find the energies of the extended states shift {\em upward}, and the amount of levitation is proportional to $(n+1/2)/B^3$ for strong magnetic field, where $B$ is the magnetic field strength and $n$ is the Landau level index.

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F. D. M. Haldane, Kun Yang. 1996-06-21. Landau Level Mixing and Levitation of Extended States in Two Dimensions. https://doi.org/10.1103/physrevlett.78.298

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