Magnetocaloric effect in the J(x) - J(y) Blume-Capel model

The magnetocaloric properties of the J(x) - J(y) Blume-Capel model with J(x)/J(y) = -0.5 are studied using the two point approximation of the Cluster Variation Method. The phase diagrams exhibit different phases depending on the anisotropy parameter, magnetic field, temperature and exchange interaction ratio. It is shown how the nature of the phase transition changes as parameters are varied. For an anisotropy parameter value of D = 1.45, a tricritical point and a reentrant behavior are identified. It was found inverse and direct magnetocaloric effect. The inverse magnetocaloric effect of the model is enhanced at low fields and temperatures around jumps between plateaus of magnetization. (c) 2023 The Author(s). Published by Elsevier B.V.

Automated summary

The magnetocaloric properties of the J(x) - J(y) Blume-Capel model with J(x)/J(y) = -0.5 were investigated using the two point approximation of the Cluster Variation Method. The phase diagrams exhibited different phases depending on the anisotropy parameter, magnetic field, temperature, and exchange interaction ratio. The study found a tricritical point and reentrant behavior for a specific anisotropy parameter value of D = 1.45, and observed both inverse and direct magnetocaloric effects, with the inverse effect being enhanced at low fields and temperatures around jumps between magnetization plateaus.