Large Anomalous Hall Effect in Topologically Trivial Double- Magnets
arXiv:2512.10168
Abstract
Multi- magnets consist of superposed spin density waves with distinct magnetic modulation vectors, enabling a wide range of magnetic orders depending on their combination. Among them, topologically nontrivial spin textures, such as a magnetic skyrmion, has been extensively studied owing to the emergence of topological Hall effects induced by real-space scalar spin chirality. Contrary to this expectation, we theoretically investigate another route to enhancing the Hall response under a topologically \textit{trivial} double- spin textures. Despite the cancellation of the scalar spin chirality, the double- magnetism exhibits a pronounced Hall response with a nonmonotonic dependence on the uniform magnetization, which is in stark contrast to a ferromagnetic state and a single- spiral state. Analyzing the multi-orbital Kondo lattice model, we show that orbital hybridization induced by the double- superstructure enhances the Berry curvature in -space, leading to a large anomalous Hall effect. This mechanism accounts for the observed giant anomalous Hall effect in GdRuSi and GdRuGe, thereby highlighting topologically trivial double- spin textures as promising spintronic materials.
Main text: 5 pages, 3 figures. Supplementary material: 7 pages, 7 figures