Anisotropic magnetic properties and tunable conductivity in two-dimensional layered NaCrX2 (X=Te,Se,S) single crystals

Monolayer NaCrX 2 (X=Te,Se,S) were theoretically proposed to be two-dimensional intrinsic ferromagnetic semiconductors while their physical properties have not been thoroughly investigated in bulk single crystals. We report the single-crystal growth, structural, magnetic and electronic transport properties of NaCr(Te 1 − x Se x ) 2 (0 6 x 6 1) and NaCrS 2 . For NaCr(Te 1 − x Se x ) 2 , the strong perpendicular magnetic anisotropy of NaCrTe 2 can be gradually tuned to be a nearly isotropic one by Se-doping. Meanwhile, a systematic change in the conductivity with increasing x is observed, dis-playing a doping-induced metal-insulator-like transition. Under magnetic field larger than 30 kOe, both NaCrTe 2 and NaCrSe 2 can be polarized to a ferromagnetic state. While for NaCrS 2 , robust antiferromagnetism is observed up to 70 kOe and two field-induced metamagnetic transitions are identified along H k ab. These intriguing properties together with the potential to be exfoliated down to few-layer thickness make NaCrX 2 (X=Te,Se,S) promising for exploring spintronic applications.