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arXiv · 1201.5175

Generalization of Chiral Symmetry for Tilted Dirac Cones

Tohru Kawarabayashi·Yasuhiro Hatsugai·Takahiro Morimoto·Hideo Aoki
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Abstract

The notion of chiral symmetry for the conventional Dirac cone is generalized to include the tilted Dirac cones, where the generalized chiral operator turns out to be non-hermitian. It is shown that the generalized chiral symmetry generically protects the zero modes (n=0 Landau level) of the Dirac cone even when tilted. The present generalized symmetry is equivalent to the condition that the Dirac Hamiltonian is elliptic as a differential operator, which provides an explicit relevance to the index theorem.

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Tohru Kawarabayashi, Yasuhiro Hatsugai, Takahiro Morimoto, Hideo Aoki. 2012-01-25. Generalization of Chiral Symmetry for Tilted Dirac Cones. https://doi.org/10.1142/s2010194512006046

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