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Redistributing Chern numbers of Landau subbands: tight-binding electrons under staggered-modulated magnetic fields

Yi-Fei Wang·Chang-De Gong
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Abstract

We investigate the magneto-transport properties of electrons on a square lattice under a magnetic field with the alternate flux strength $ϕ\pmΔϕ$ in neighboring plaquettes. A new peculiar behavior of the Hall conductance has been found and is robust against weak disorder: if $ϕ={p\over{2N}}\times{2π}$ ($p$ and $2N$ are coprime integers) is fixed, the Chern numbers of Landau subbands will be redistributed between neighboring pairs and hence the total quantized Hall conductance exhibits a direct transition by $\pm{N}e^2/h$ at critical fillings when $Δϕ$ is increased from 0 up to a critical value $Δϕ_c$. This effect can be an experimental probe of the staggered-flux phase.

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Yi-Fei Wang, Chang-De Gong. 2007-03-19. Redistributing Chern numbers of Landau subbands: tight-binding electrons under staggered-modulated magnetic fields. https://doi.org/10.1103/physrevlett.98.096802

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