Field‐Induced Butterfly‐Like Anisotropic Magnetoresistance in a Kagome Semimetal Co₃In₂S₂

Abstract With the interplay between magnetism and topological bands, magnetic kagome semimetals provide promising platforms for exploring exotic correlated electronic states and quantum phenomena such as anomalous Hall effect, quantum spin liquid, and unconventional magnetoresistance, as well as driving advances in electronic and spintronic applications. Here, a field‐induced butterfly‐like anomalous anisotropic magnetoresistance (AMR) effect in an intriguing kagome semimetal Co 3 In 2 S 2 is reported. The kagome‐lattice Co 3 In 2 S 2 single crystals are synthesized via a polycrystal‐source chemical vapor transport approach, possessing a high carrier mobility reaching 10 4 cm 2 V −1 s −1 . The Co 3 In 2 S 2 single crystal exhibits a canted antiferromagnetic state below 5 K, but intriguingly, it is easily transformed into a ferromagnetic state under a small external magnetic field. Furthermore, the planar Hall effect (PHE) is detected, stemming from the complex contribution of field‐induced ferromagnetism and orbital magnetoresistance. Remarkably, as the magnetic field increases, the low‐temperature magnetoresistance behavior of the Co 3 In 2 S 2 reveals a butterfly‐like AMR effect with a maximum value of 850%, exhibiting a superposition of the two‐, four‐, and six‐fold AMR terms. Band structure calculations suggest that such a field‐induced butterfly‐like AMR effect may originate from the modulations of the electronic structure near the Fermi level by the magnetic moment. The findings offer a valuable platform for understanding the anomalous AMR effect and for the development of advanced spintronic devices.