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arXiv · 1608.08633

Strain-induced Landau Levels in arbitrary dimensions with an exact spectrum

Stephan Rachel·Ilja Goethel·Daniel P. Arovas·Matthias Vojta
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Abstract

Certain non-uniform strain applied to graphene flakes has been shown to induce pseudo-Landau levels in the single-particle spectrum, which can be rationalized in terms of a pseudo-magnetic field for electrons near the Dirac points. However, this Landau level structure is in general approximate and restricted to low energies. Here we introduce a family of strained bipartite tight-binding models in arbitrary spatial dimension d and analytically prove that their entire spectrum consists of perfectly degenerate pseudo-Landau levels. This construction generalizes the case of triaxial strain on graphene's honeycomb lattice to arbitrary d; in d=3 our model corresponds to tetraxial strain on the diamond lattice. We discuss general aspects of pseudo-Landau levels in arbitrary d.

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Stephan Rachel, Ilja Goethel, Daniel P. Arovas, Matthias Vojta. 2017-01-04. Strain-induced Landau Levels in arbitrary dimensions with an exact spectrum. https://doi.org/10.1103/physrevlett.117.266801

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