Topologically protected spin whirls in ferromagnets are foreseen as the cart-horse of solitonic information technologies. Nevertheless, the future of skyrmionics may rely on antiferromagnets due to their immunity to dipolar fields, straight motion along the driving force and ultrafast dynamics. While complex topological objects were recently discovered in intrinsic antiferromagnets, mastering their nucleation, stabilization and manipulation with energy-efficient means remains an outstanding challenge. Designing topological polar states in magnetoelectric antiferromagnetic multiferroics would allow one to electrically write, detect and erase topological antiferromagnetic entities. Here we stabilize ferroelectric centre states using a radial electric field in multiferroic BiFeO₃ thin films. We show that such polar textures contain flux closures of antiferromagnetic spin cycloids, with distinct antiferromagnetic entities at their cores depending on the electric field polarity. By tuning the epitaxial strain, quadrants of canted antiferromagnetic domains can also be electrically designed. These results open the path to reconfigurable topological states in multiferroic antiferromagnets.

铁磁体中受拓扑保护的自旋涡流被预见为孤子信息技术的主力。尽管如此，斯格明子学的未来可能依赖于反铁磁体，因为它们不受偶极场的影响，沿驱动力直线运动和超快动力学。虽然最近在本征反铁磁体中发现了复杂的拓扑物体，但通过节能手段掌握其成核、稳定和操纵仍然是一个突出的挑战。在磁电反铁磁多铁性材料中设计拓扑极性态将允许人们以电方式写入、检测和擦除拓扑反铁磁实体。在这里，我们使用多铁性 BiFeO ₃薄膜中的径向电场来稳定铁电中心态。我们表明，这种极性纹理包含反铁磁自旋摆线的磁通闭合，根据电场极性，其核心具有不同的反铁磁实体。通过调整外延应变，还可以对倾斜反铁磁畴的象限进行电气设计。这些结果为多铁性反铁磁体的可重构拓扑态开辟了道路。