Abundance of Weyl points in semiclassical multi-terminal superconducting nanostructures

Hristo Barakov; Yuli V. Nazarov

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arXiv · 2112.13928

Abundance of Weyl points in semiclassical multi-terminal superconducting nanostructures

Hristo Barakov·Yuli V. Nazarov

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Abstract

We show that the quasi-continuous gapless spectrum of Andreev bound states in multi-terminal semi-classical superconducting nanostructures exhibits a big number of topological singularities. We concentrate on Weyl points in a 4-terminal nanostructure, compute their density and correlations in 3D parameter space for a universal RMT model as well as for the concrete nanostructures described by the quantum circuit theory. We mention the opportunities for experimental observation of the effect in a quasi-continuous spectrum.

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Hristo Barakov, Yuli V. Nazarov. 2021-12-27. Abundance of Weyl points in semiclassical multi-terminal superconducting nanostructures. https://arxiv.org/abs/2112.13928

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