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arXiv · 2608.22783

A Topological Magnonic Black-White Hole Crystal

D. Galvez-Poblete·R. M. Otxoa·A. S. Nunez·S. Allende
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Abstract

The low-energy dynamics of antiferromagnetic spin waves map onto a massive Klein-Gordon scalar field, providing a solid-state platform for analogue-horizon physics. We show that an inhomogeneous spin current generates an effective magnon flow capable of forming black- and white-hole horizons. Horizon-pair cavities exhibit resonant transport and superradiant-like amplification mediated by magnon-antimagnon mixing. Our central result is that a periodic arrangement of submagnonic and supermagnonic regions forms a non-reciprocal magnonic crystal in which entering the supermagnonic regime makes negative-norm propagating channels available and enables the bulk gap to close and reopen. This drives a topological transition characterized by a change in the Zak phase and the emergence of a hybrid magnon-antimagnon edge state. These results establish a direct connection between analogue-horizon physics and topological magnonics, providing an electrically tunable route for controlling magnonic band topology.

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D. Galvez-Poblete, R. M. Otxoa, A. S. Nunez, S. Allende. 2026-08-24. A Topological Magnonic Black-White Hole Crystal. https://arxiv.org/abs/2608.22783

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