Field-dependent characteristics of equivalent circuit parameters and the magneto-impedance effect in Tb1-xDyxFe2-y/Pb(Zr,Ti)O3 laminate vibrator

Introduction: Impedance curves, equivalent circuit parameters in Tbi-xDyxFe2-y/Pb(Ti-x,Zr1-x)O-3 laminate vibrator have been characterized as a function of external DC magnetic field. Clearly, the equivalent circuit parameters are function of external DC magnetic field due to the field-dependent properties of magnetostrictive material. Conclusion: Based on these researches, the magneto-impedance (MI) effect is observed in the laminate vibrator, i.e., the impedance across the electrodes of the piezoelectric layer strongly depends on DC magnetic field. Analysis shows that the MI effect is primarily attributed to the field dependence of magneto-mechanical damping in Tb1-xDyxFe2-y. The experimental results show that the maximum MI ratios up to 280% and 222.4% along with the sensitivities correspondent to DC magnetic field up to 1.71% 0e(-1) and 0.8% 0e(-1) are obtained at the selected operating frequencies around the frequencies of maximum and minimum impedances. The results open up possibilities for a new type of Ml devices, magnetic field sensors, or multi-functional ferromagnetic/piezoelectric composite devices. (C) 2015 Elsevier B.V. All rights reserved.