Magnetodielectric effect and electric-induced magnetic permeability in magnetoelectric laminate composite under low inspiring signal

A theory based on equivalent circuit was proposed to demonstrate that magnetodielectric (MDE) effect and electric-induced magnetic permeability (EIMP) exist in the magnetoelectric composite. Both MDE and EIMP are sensitive to the amplitude of inspiring signal. They were researched in a simple Pb(Zr,Ti)O3/Terfenol-D laminate composite experimentally. A large MDE coefficient over 85% was found near the resonance frequency under a low magnetic field of 40 Oe. The EIMP was also observed in the composite. They are mainly originated from the magnetoelectric coupling between the piezoelectric and magnetostrictive components. These results are significant in the device applications of modulating dielectric constant and magnetic permeability at room temperature.