Enhanced magnetoelectric effect in three-phase MnZnFe2O4/Tb1-xDyxFe2-y/Pb(Zr,Ti)O3 composites

Three-phase magnetoelectric (ME) laminate composites made of high-permeability (mu) MnZnFe2O4, magnetostrictive Tb1-xDyxFe2-y, and piezoelectric Pb(Zr,Ti)O-3 layers and operated in longitudinal magnetization and transverse polarization (L-T) bending modes have been studied. High-mu MnZnFe2O4 layers act as flux concentrators. This results in increased apparent piezomagnetic coefficients in the magnetostrictive Tb1-xDyxFe2-y layer and consequently larger induced voltages across the piezoelectric Pb(Zr,Ti)O-3 layers. We find the enhanced ME field coefficients of up to 8 times for longitudinal magnetization mode, and up to 28 times for transverse magnetization mode, under small dc magnetic field bias. (c) 2006 American Institute of Physics.