Correlation between magnetoelectric and magnetic properties of ferromagnetic-piezoelectric structures

The magnetoelectric (ME) effect in composite structures consisting of ferromagnetic (FM) and piezoelectric (PE) layers arises due to combination of magnetostriction and piezoelectricity by means of mechanical coupling between the layers. The structures generate ac voltage u being placed in an external dc bias magnetic field H and ac magnetic field h. Amplitude of the voltage is u ~qd₃₁h, where q = dλ/dH is the piezomagnetic coefficient and λ(H) in the magnetostriction of the FM layer, d₃₁ is the piezoelectric module of the PE layer, and h is the field amplitude. It has been shown that the magnetostriction is related to the FM layer magnetization as λ ~ M ². It follows, that field dependence of the ME voltage u(H) can be explained or predicted by measuring the field dependence of magnetization M(H). The aim of the present work is to demonstrate a correlation between magnetoelectric and magnetic properties of the FM-PE composite structures.