Magnetic evolution of Cr2Te3 epitaxially grown on graphene with post-growth annealing.

Two-dimensional and van der Waals ferromagnets are ideal platform to study low-dimensional magnetism and proximity effects in van der Waals heterostructures. Their ultimate two-dimensional character also offers the opportunity to easily adjust their magnetic properties using strain or electric fields. Among 2D ferromagnets, the Cr 1 + x Te₂ compounds with x = 0–1 are very promising because their magnetic properties depend on the amount of self-intercalated Cr atoms between pure CrTe₂ layers and the Curie temperature ( T C ) can reach room temperature for certain compositions. Here, we investigate the evolution of the composition as well as the structural and magnetic properties of thin Cr_1.33Te₂ (Cr₂Te₃) films epitaxially grown on graphene upon annealing. We observe a transition above 450 °C from the Cr_1.33Te₂ phase with perpendicular magnetic anisotropy and a T C of 180 K to a composition close to Cr 1.39 Te₂ with in-plane magnetic anisotropy and a T C of 240–250 K. This phase remains stable up to 650 °C above which a pure Cr film starts to form. This work demonstrates the complex interplay between intercalated Cr, lattice parameters, and magnetic properties in Cr 1 + x Te₂ compounds. [ABSTRACT FROM AUTHOR]