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arXiv · 2608.21200

Symmetry-Induced Weyl Nodes in Interacting Multi-Terminal Josephson Junctions

Peter Zalom·Gustavo Diniz·David Christian Ohnmacht·Wolfgang Belzig
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Abstract

We show that an emergent geometric symmetry generates non-trivial topology in quantum-dot-based multi-terminal Josephson junctions. It confines same-spin Andreev bound state crossings to an analytic one-dimensional manifold of the synthetic Brillouin zone, where interdot coupling selects Weyl nodes of charge $\pm1$ in the singlet sector and doubly degenerate cones of charge $\pm2$ in the doublet sector, at gate-tunable locations. The mechanism yields a spectroscopic detection protocol and a design principle for fabricating devices with non-trivial topological signatures.

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Peter Zalom, Gustavo Diniz, David Christian Ohnmacht, Wolfgang Belzig. 2026-08-21. Symmetry-Induced Weyl Nodes in Interacting Multi-Terminal Josephson Junctions. https://arxiv.org/abs/2608.21200

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