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arXiv · 0708.0216

Modulation effects on Landau levels in a monolayer graphene

J. H. Ho·Y. H. Lai·Y. H. Chiu·M. F. Lin
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Abstract

A monolayer graphene exists in an environment where a uniform magnetic field interacts a spatially modulated magnetic field. The spatially modulated magnetic field could affect Landau levels due to a uniform magnetic field. The modulation effects on Landau levels are investigated through the Peierl's tight-binding model. The magneto-electronic properties are dominated by the period, the strength, and the direction of a spatially modulated magnetic field. Such a field could induce the growth in dimensionality, the change of energy dispersions, the destroy of state degeneracy, and the creation of band-edge states. There are a robust Landau level at Fermi level and 1D parabolic subbands located around the original Landau levels, which make density of states exhibit a delta-function-like structure and many pairs of asymmetric peak structure, respectively. The density of states and the energies of band-edge states strongly depend on the strength, but not on the period and the direction.

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J. H. Ho, Y. H. Lai, Y. H. Chiu, M. F. Lin. 2007-08-01. Modulation effects on Landau levels in a monolayer graphene. https://arxiv.org/abs/0708.0216

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