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arXiv · 2401.12569

Magnetic Dirac systems: Violation of bulk-edge correspondence in the zigzag limit

Loïc Le Treust·Jean-Marie Barbaroux·Horia D. Cornean·Edgardo Stockmeyer·Nicolas Raymond
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Abstract

We consider a Dirac operator with constant magnetic field defined on a half-plane with boundary conditions that interpolate between infinite mass and zigzag. By a detailed study of the energy dispersion curves we show that the infinite mass case generically captures the profile of these curves, which undergoes a continuous pointwise deformation into the topologically different zigzag profile. Moreover, these results are applied to the bulk-edge correspondence. In particular, by means of a counterexample, we show that this correspondence does not always hold true in the zigzag case.

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Loïc Le Treust, Jean-Marie Barbaroux, Horia D. Cornean, Edgardo Stockmeyer, Nicolas Raymond. 2024-01-23. Magnetic Dirac systems: Violation of bulk-edge correspondence in the zigzag limit. https://arxiv.org/abs/2401.12569

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