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arXiv · 2211.04947

Protected Topological Nodal Ring Semimetal in Graphene

Karyn Le Hur·Sariah Al Saati
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Abstract

Graphene is a two-dimensional Dirac semimetal showing interesting properties as a result of its dispersion relation with both quasiparticles and quasiholes or matter and anti-matter. We introduce a topological nodal ring semimetal in graphene with a quantized quantum Hall response, a robust one-dimensional chiral edge mode and a quadratic Fermi-liquid spectrum for the quasiparticles and quasiholes in the bulk. The bulk band degeneracy at the Fermi energy is protected through a Z2 symmetry related to the two spin polarizations of an electron and a double-orthogonality structure in the sublattice and spin quantum numbers of the two crossing eigenstates. The system may have applications in nano-electronics and in quantum mechanical entanglement applied to band theory.

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Karyn Le Hur, Sariah Al Saati. 2022-11-09. Protected Topological Nodal Ring Semimetal in Graphene. https://doi.org/10.1103/physrevb.107.165407

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