Study of Entropy Production of Magnetoelectric Multiferroic Materials

Composite multiferroic materials were prepared using the conventional ceramic double sintering process, with composition of Ґ BaTiO₃/(1 − Ґ) Cu_0.3Ni_0.1Zn_0.6Fe₂O₄, where Ґ represents the mass fraction of the ferroelectric phase ranging from 0.3 to 0.9. The behavior of the bulk composites under external dynamic magnetic and electric fields was studied as a function of the ferroelectric phase content. The objective of this work is to establish a relationship between the irreversibility process and magnetic and electrical losses in composite magnetoelectric materials. Experimental measurements were correlated with the entropy production of materials. The results allow us to infer that in the explored frequency range (from 1 MHz to 1.8 GHz), entropy production not only decreases as the ferroelectric phase content increases but is also related to the magnetic losses.