A phenomenological model for the magnetodielectric effect in magnetoelectric composites

This paper proposes a phenomenological description for the nonlinear dielectric permittivity dependence on magnetic field, also called Magnetodielectric (MD) Effect, in strain mediated magnetoelectric composites. The description is derived by incorporating the dielectric dependence on electric polarization, thermodynamic constitutive equations, and magneto-mechanical effects. Moreover, the proposed expression successfully re-produces the experimental behavior reported in existing literature and can provide an explanation for the observed anisotropic effect. Simulations performed using the derived expression demonstrate an inherent cor-relation between the coupling of piezoelectric and magnetostrictive coefficients and the observed MD coefficient curves as measured in experiments. The validity of the model was verified by application to KNN/CFO and KNN/ NFO multiferroic particulate composite samples.