Unveiling a Scaling and Universal Behavior for the Magnetocaloric Effect in Cubic Crystal Structures: A Monte Carlo Simulation

Abstract

The magnetocaloric effect and the universal character for the magnetic entropy change regarding the cubic crystal structures (SC, BCC, FCC) were investigated, in a qualitative way, using Monte Carlo simulations. A classical Heisenberg Hamiltonian with nearest neighbors, and next nearest neighbors interactions was implemented. In order to compute the critical temperature of the system depending on the coordination number, it was calculated the dependence of the magnetization and magnetic susceptibility as a function of temperature. Magnetic field dependence on the magnetization for isothermal processes was performed considering a magnetocrystalline anisotropy term. In this way, the magnetic entropy change (Δ S m ) was computed. Results show that the rescaled Δ S m as well as the exponent ( n ) characterizing the field dependence of the magnetic entropy change curves, collapse onto a single curve for the studied crystal structures. By this reason, it can be assured that Δ S m exhibits a universal behavior regarding the strength and contribution of the magnetic exchange energy to the total magnetic energy.

On the structural and magnetic properties of Al-rich high entropy alloys: a joint experimental-theoretical study

“…Rh and also with tunable magnetic properties according to exact composition [21]. For example, Huang et al [13] reported that the meltspun Al 0.44 Cr 0.25 MnFeCo 0.25 Ni 0.2 alloy with the BCC structure has ∆S M of 0.458 Jkg −1 K −1 , and RCP of 27 Jkg −1 at a magnetic field of ∼0.82 T. Recent studies suggest that ∆S M is larger for HEAs in the BCC structure in comparison with that in the FCC structure due to the larger coordination number of the FCC structure [22]. For example, Na et al [23] studied the structural and magnetocaloric properties of the AlCrFeCoNi HEA.…”