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arXiv · 1904.12784

Dirac and Weyl Fermions in 3D Hopf-linked Honeycomb Lattices: Hopfene

Shinichi Saito·Isao Tomita
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Abstract

Carbon allotropes such as diamond, nano-tube, Fullerene, and Graphene, have unique lattice symmetries of crystal lattice, but these are topologically trivial. We have proposed a topologically-nontrivial allotrope, named Hopfene, which has three-dimensional (3D) arrays of Hopf-links to bind 2D Graphene sheets both vertically and horizontally. Here, we describe the electronic structures of Hopfene by simple tight-binding calculations. We confirmed the original Dirac points of 2D Graphene were topologically protected upon the introduction of the Hopf links, and low-energy excitations are described by 1D, 2D, and 3D Dirac and Weyl Fermions.

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Shinichi Saito, Isao Tomita. 2019-04-29. Dirac and Weyl Fermions in 3D Hopf-linked Honeycomb Lattices: Hopfene. https://arxiv.org/abs/1904.12784

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