Magnetic critical behavior of van der Waals Fe₃GaTe₂ with above-room-temperature ferromagnetism

Fe3GaTe2 is a promising van der Waals material for future spintronic applications because of its intrinsic above-room-temperature ferromagnetism. Herein, high quality Fe3GaTe2 single crystals were successfully grown by the chemical vapor transport method. Its magnetic critical behavior in the vicinity of paramagnetic to ferromagnetic phase transition region was systematically investigated. The critical exponents beta = 0.350(1) and gamma = 1.385(5) were obtained by using the Kouvel-Fisher method, and delta = 4.92(1) was obtained by a critical isotherm analysis at critical temperature T-C = 358 K, which is consistent with the Widom scaling relation delta = 1 + gamma/beta. The critical exponents determined using different methods are self-consistent and obey the scaling equations predicted by the scaling theory. The renormalization group theory analysis based on the extracted critical exponents further reveals that the magnetic interaction in Fe3GaTe2 is of the 3D Heisenberg type with long-range magnetic coupling.