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arXiv · 2602.02939

Highly controllable switching pathways in multiferroic GdMn$_2$O$_5$

M. Ryzhkov·A. Granero·J. Wettstein·Anna Pimenov·X. Wang·L. Ponet·S. -W. Cheong·M. Mostovoy·Andrei Pimenov·S. Artyukhin
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Abstract

Controlling magnetic moments using electric fields remains a central challenge in spintronics. Multiferroics, where magnetic and electric orders coexist, may be a natural platform for such control, but progress has been limited because interactions between these orders are typically too weak to overcome the energy barriers between magnetic states. A recently demonstrated topologically protected switching circumvents this limitation by exploiting reduced barriers at a phase transition. Nevertheless, the conditions enabling this phenomenon remain elusive and electric field control is poorly understood. Here, we experimentally map the energy landscape by tracking transitions in GdMn$_2$O$_5$ under combined electric and magnetic fields. The experiments reveal that the switching pathways can be controlled by the electric field. A minimal theoretical model captures the observed behavior, identifies the parameter space where switching paths are sensitive to small perturbations and reveals design principles for implementing topological switching in other materials.

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M. Ryzhkov, A. Granero, J. Wettstein, Anna Pimenov, X. Wang, L. Ponet, S. -W. Cheong, M. Mostovoy, Andrei Pimenov, S. Artyukhin. 2026-02-25. Highly controllable switching pathways in multiferroic GdMn$_2$O$_5$. https://arxiv.org/abs/2602.02939

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