Critical behavior and magnetocaloric effect in VI3

Abstract

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 β=0.244(5) with a critical temperature Tc=50.10(2)K and γ=1.028(12) with Tc=49.97(5)K are obtained from the modified Arrott plot, whereas δ=5.24(2) is obtained from a critical isotherm analysis at Tc=50K. The magnetic entropy change -ΔSM(T,H) features a maximum at Tc, i.e., -ΔSMmax∼2.64(2.27)Jkg-1K-1 with out-of-plane (in-plane) field change of 5 T. This is consistent with -ΔSMmax∼2.80Jkg-1K-1 deduced from heat capacity and the corresponding adiabatic temperature change ΔTad∼0.96K 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 ΔSM(T,H) curves collapse onto a universal curve, confirming a second-order type of the magnetic transition and reliability of the obtained critical exponents.