Anisotropic Magnetoresistance and Giant Topological Hall Effect in In-Plane Topological Spin Structures

Topologically protected spin textures hold great potential in functional spintronic applications. Previous research has centered on skyrmions in perpendicularly magnetized systems. However, the formation and transport properties of topological spin structures in in-plane magnetized systems remain largely unexplored. Here, we systematically investigate the spin configurations and transport properties of FeCo-based systems through combined thickness and interface engineering. Cross-tie domain walls form in FeCo single layers, while meron chains emerge in FeCo/W heterostructures, leading to distinct anisotropic spin transport. By conducting angular-dependent analysis of Hall signals, we successfully distinguish the contribution from planar, anomalous, and topological Hall effects, enabling efficient detection of in-plane topological spin textures through transport characterizations. A giant topological Hall resistivity of ∼0.24 μΩ·cm is obtained in the heterostructure at room temperature. Our results have clarified the complex transport characteristics in topologically nontrivial in-plane magnets while opening new avenues for exploring magnetotransport phenomena in condensed matter systems.