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New universality of metal-insulator transition in integer quantum Hall effect system

D. N. Sheng·Z. Y. Weng
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Abstract

A new universality of metal-insulator transition in integer quantum Hall effect (IQHE) system is studied based on a lattice model, where the IQHE states only exist within a finite range of Fermi energy in the presence of disorders. A two-parameter scaling law is found at the high-energy boundary where direct transitions from high IQHE states to insulator occur. We find $ρ_{xx}= ρ_{xy}$ at the critical point whose value can continuously vary as a single function of the Landau-level filling number $n_ν$. Such a new universality well explains recent experiment by Song et al. (Phys. Rev. Lett. 78, 2200 (1997)).

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D. N. Sheng, Z. Y. Weng. 1997-10-11. New universality of metal-insulator transition in integer quantum Hall effect system. https://doi.org/10.1103/physrevlett.80.580

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