Related papers: Spectral properties of hexagonal lattices with the -R coupling

Spectral properties of hexagonal lattices with the -R coupling

URL: http://arxiv.org/abs/2409.03538v1
Date: Thu, 5 Sep 2024 13:55:57 GMT
Title: Spectral properties of hexagonal lattices with the -R coupling
Authors: Pavel Exner, Jan Pekař,
Abstract summary: We show that the spectral character does not change if the equilateral elementary cell of the lattice is dilated to have three different edge lengths, except that flat bands are absent if those are incommensurate. We also show that the spectral character does not change if the equilateral elementary cell of the lattice is dilated to have three different edge lengths, except that flat bands are absent if those are incommensurate.
Score: 0.0
License: http://creativecommons.org/licenses/by/4.0/
Abstract: We analyze the spectrum of the hexagonal lattice graph with a vertex coupling which manifestly violates the time reversal invariance and at high energies it asymptotically decouples edges at even degree vertices; a comparison is made to the case when such a decoupling occurs at odd degree vertices. We also show that the spectral character does not change if the equilateral elementary cell of the lattice is dilated to have three different edge lengths, except that flat bands are absent if those are incommensurate.

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