The Magneto-Transport Properties of Cr_1/3TaS₂ with Chiral Magnetic Solitons

Cr_1/3TaS₂—a candidate of chiral magnet—has been reported as a trivial ferromagnetic material. In contrast, the Cr_1/3TaS₂ single crystals exhibit a chiral helimagnetic (CHM) transition near 140 K. The magnetic moment versus magnetic field curves reveal a CHM—chiral soliton lattice (CSL)—forced ferromagnetic (FFM) transition in the magnetic ordered state. The conducting electrons interact with the CHM and CSL orders, giving rise to the nontrivial magnetoresistance (MR) in the Cr_1/3TaS₂ single crystals. The normalized magnetic moment and normalized MR fit well with the analytical functions for chiral soliton density. The magnetic phase diagrams constructed from the magnetic moment data and MR data suggest a possible tri-critical point. Compared with the isostructural Cr_1/3NbS₂, the CHM transition temperature of Cr_1/3TaS₂ is 13 K higher, the CSL—FFM transition field is about 10 times larger, and the Dzyaloshinskii-Moriya interaction strength is 3 times bigger. The latter two likely originate from the strong spin-orbit coupling (SOC) of Cr_1/3TaS₂. The work clarifies that high-quality Cr_1/3TaS₂ single crystals are chiral magnets and Cr_1/3(Nb,Ta)S₂ could serve as an intriguing platform for the flexible engineering of chiral magnetic solitons with tunable SOC.