Resonant magnetoelectric coupling in trilayers of ferromagnetic alloys and piezoelectric lead zirconate titanate: The influence of bias magnetic field

We present the first data and theory for the bias magnetic field dependence of magnetoelectric coupling in the electromechanical resonance (EMR) region for ferromagnetic-piezoelectric heterostructures. Trilayers of Permendur, a Co-Fe-V alloy, and lead zirconate titanate were studied. Measurements of the magnetoelectric (ME) voltage coefficient alpha(E) indicate a strong ME coupling in the low-frequency range and a giant ME effect due to EMR at 200-300 kHz for radial modes and at similar to 2.7 MHz for thickness modes. Data were obtained for the bias field H dependence of two key parameters, the EMR frequency f(r) and the ME coefficient alpha(E,R) at resonance. With increasing H, an increase in f(r) and a rapid rise and fall in alpha(E,R) are measured. In our model we consider two mechanisms for the magnetic field influence on ME interactions: (i) a shift in the EMR frequency due to changes in compliance coefficients (Delta E effect) and (ii) variation in the piezomagnetic coefficient that manifests as a change in alpha(E,R). Theoretical profiles of alpha E vs frequency and estimates of frequency shift based on the Delta E effect are in excellent agreement with the data.