Critical behavior of the van der Waals ferromagnet Cr_1.2Te₂

The van der Waals ferromagnet CrTe₂ is a promising candidate due to its high Curie temperature at room temperature and large magnetic moment. Furthermore, the magnetic anisotropy can be adjusted by the concentration of Cr ion. To understand the ferromagnetic exchange mechanism involving the self-intercalation of Cr atoms into CrTe₂, we systematically investigated the critical behavior of Cr_1.2Te₂. We obtained a set of reliable critical exponent values (β = 0.882(3), γ = 1.201(6), and δ = 2.36(4)) by using diverse analytical methods. The critical behavior suggests a three-dimensional magnetic exchange mechanism in Cr_1.2Te₂, with the exchange distance decaying approximately as J(r) ≈ r^− 4.70. This behavior closely resembles the 3D Heisenberg model with long-range magnetic coupling.