Work

Electrically driven topological magnetic knots in BiFeO3 films

Year: 2026

Type: article

Abstract: The fundamental nature of dynamic magnetoelectric coupling in multiferroics remains poorly understood. Despite these compelling static observations, its stability is governed by the convergence of the propagation direction ( k ) and the topology of the polarization structure, originating from the intertwining of π-disclinations. Strikingly, the knot exhibits synchronous propagation with ferroelectric domain walls under external electric fields, effectively preserving its topological integrity. Leveraging the topological nature of polarization order together with strong magnetoelectric coupling, a universal mechanism is manifested for the realization of nontrivial magnetic topological structures and their cooperative dynamics that should be operative across diverse topological materials. Our findings reveal a robust topology-mediated magnetoelectric dynamical mechanism, shedding light on the non-equilibrium physics of multiferroics and opening avenues for topological spintronics.

Source: npj Computational Materials

DOI: 10.1038/s41524-026-02279-4