Critical behavior and magnetocaloric effect in VI3

Layered van der Waals ferromagnets are promising candidates for designing new spintronic devices. Here we investigated the critical properties and magnetocaloric effect connected with ferromagnetic transition in layered van der Waals VI3 single crystals. The critical exponents beta = 0.244(5) with a critical temperature T-c = 50.10(2) K and gamma = 1.028(12) with T-c = 49.97(5) K are obtained from the modified Arrott plot, whereas delta = 5.24(2) is obtained from a critical isotherm analysis at T-c = 50 K. The magnetic entropy change - Delta S-M(T, H) features a maximum at T-c, i.e., - Delta S-M(max) similar to 2.64(2.27) J kg(-1) K-1 with out-of-plane (in-plane) field change of 5 T. This is consistent with - Delta S-M(max) similar to 2.80 J kg(-1) K-1 deduced from heat capacity and the corresponding adiabatic temperature change Delta T-ad similar to 0.96 K with out-of-plane field change of 5 T. The critical analysis suggests that the ferromagnetic phase transition in VI3 is situated close to a three- to two-dimensional critical point. The rescaled Delta S-M(T, H) curves collapse onto a universal curve, confirming a second-order type of the magnetic transition and reliability of the obtained critical exponents.