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arXiv · 2106.16019

Kagome network with vertex coupling of a preferred orientation

Marzieh Baradaran·Pavel Exner
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Abstract

We investigate spectral properties of periodic quantum graphs in the form of a kagome or a triangular lattice in the situation when the condition matching the wave functions at the lattice vertices is chosen of a particular form violating the time-reversal invariance. The positive spectrum consists of infinite number of bands, some of which may be flat; the negative one has at most three and two bands, respectively. The kagome lattice example shows that even in graphs with such an uncommon vertex coupling spectral universality may hold: if its edges are incommensurate, the probability that a randomly chosen positive number is contained in the spectrum is $\approx 0.639$.

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Marzieh Baradaran, Pavel Exner. 2021-06-30. Kagome network with vertex coupling of a preferred orientation. https://doi.org/10.1063/5.0093546

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