Related papers: Vertex coupling interpolation in quantum chain graphs

Vertex coupling interpolation in quantum chain graphs

URL: http://arxiv.org/abs/2403.09457v1
Date: Thu, 14 Mar 2024 14:58:39 GMT
Title: Vertex coupling interpolation in quantum chain graphs
Authors: Pavel Exner, Jan Pekař,
Abstract summary: We analyze band spectrum of the periodic quantum graph in the form of a chain of rings connected by line segments with the $delta$ coupling. We find that flat bands are generically absent and that the negative spectrum is nonempty even for with a non-attractive $delta$ coupling.
Score: 0.0
License: http://creativecommons.org/licenses/by/4.0/
Abstract: We analyze band spectrum of the periodic quantum graph in the form of a chain of rings connected by line segments with the vertex coupling which violates the time reversal invariance, interpolating between the $\delta$ coupling and the one determined by a simple circulant matrix. We find that flat bands are generically absent and that the negative spectrum is nonempty even for interpolation with a non-attractive $\delta$ coupling; we also determine the high-energy asymptotic behavior of the bands.

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