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arXiv · 2403.09457

Vertex coupling interpolation in quantum chain graphs

Pavel Exner·Jan Pekař
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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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Pavel Exner, Jan Pekař. 2024-03-14. Vertex coupling interpolation in quantum chain graphs. https://arxiv.org/abs/2403.09457

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