Singha, R.; Dalgaard, K.J.; Marchenko, D.; Krivenkov, M.; Rienks, E.D.L.; Jovanovic, M.; Teicher, S.M.L.; Hu, J.; Salters, T.H.; Lin, J.; Varykhalov, A.; Ong, N.P.; Schoop, L.M.: Colossal magnetoresistance in the multiple wave vector charge density wave regime of an antiferromagnetic Dirac semimetal. Science Advances 9 (2023), p. eadh0145/1-8
10.1126/sciadv.adh0145
Open Access Version
Abstract:
Colossal negative magnetoresistance is a well-known phenomenon, notably observed in hole-doped ferromagnetic manganites. It remains a major research topic due to its potential in technological applications. In contrast, topological semimetals show large but positive magnetoresistance, originated from the high-mobility charge carriers. Here, we show that in the highly electron-doped region, the Dirac semimetal CeSbTe demonstrates similar properties as the manganites. CeSb0.11Te1.90 hosts multiple charge density wave modulation vectors and has a complex magnetic phase diagram. We confirm that this compound is an antiferromagnetic Dirac semimetal. Despite having a metallic Fermi surface, the electronic transport properties are semiconductor-like and deviate from known theoretical models. An external magnetic field induces a semiconductor metal–like transition, which results in a colossal negative magnetoresistance. Moreover, signatures of the coupling between the charge density wave and a spin modulation are observed in resistivity. This spin modulation also produces a giant anomalous Hall response.