Ferromagnetism and Rashba Spin-Orbit Coupling in the Two-Dimensional (V,Pt)Se-2 Alloy

We report on a two-dimensional (2D) V1-xPtxSe2 alloy that exhibits ferromagnetic order and Rashba spin-orbit coupling. Although ferromagnetism is absent in 1T-VSe2 because of the competition with the charge density wave phase, we demonstrate theoretically and experimentally that the substitution of vanadium by platinum in VSe2 (10-50%) to form a homogeneous 2D alloy restores ferromagnetic order down to one monolayer of V0.65Pt0.35Se2. Moreover, the presence of platinum atoms gives rise to Rashba spin-orbit coupling in (V,Pt)Se-2, providing an original platform to study the interplay between ferromagnetism and spin-orbit coupling in the 2D limit.