Observation of distinct Kondo effect and anomalous Hall effect in V self-intercalated layered antiferromagnet V ₅ S ₈ crystals

Abstract Vanadium-based transition metal chalcogenides V m X n ( X = S, Se, Te) with their distinctive quantum effects, tunable magnetism, spin–orbit coupling, and high carrier mobility are a valuable platform to explore the interplay between magnetism and electronic correlations, especially with tunable structural phases and magnetic properties through stoichiometric variations, making them ideal candidates for advanced device applications. Here, we report the synthesis of high-quality V 5+ x S 8 single crystals with different concentrations of self-intercalated vanadium. V 5+ x S 8 crystals show an antiferromagnetic behavior and a spin-flop-like transition below T N of 30.6 K. The high-quality V 5+ x S 8 single crystals exhibit a large negative magnetoresistance of 12.3% at 2 K. Interestingly, V 5+ x S 8 crystals show an obvious low-temperature resistance upturn that gradually levels off with the increasing magnetic field, attributed to the Kondo effect arising from the interaction between conduction electrons and embedded vanadium magnetic impurities. With increasing V doping, the antiferromagnetic interactions intensify, weakening the coupling between the local moments and conduction electrons, which in turn lowers the Kondo temperature ( T K ). Furthermore, the anomalous Hall effect is observed in V 5.73 S 8 , with an anomalous Hall conductivity (AHC) of 50.46 Ω −1 ⋅cm −1 and anomalous Hall angle of 0.73% at 2 K. Our findings offer valuable insights into the mechanisms of the Kondo effect and anomalous Hall effect in self-intercalated transition metal chalcogenides with complex magnetism and electronic correlation effects.