Diogo Z. Montanher, Valdirlei F. Freitas, José R. Dias Pereira, Luiz F. Cótica, Ducinei Garcia, José A. Eiras e Ivair A. Santos

JOURNAL OF APPLIED PHYSICS  Volume: 113   Issue: 3     Article Number: 034102   DOI: 10.1063/1.4775796, Published: JAN 2013

The potentialities of BiFeO₃-PbTiO₃ multiferroic compounds for magnetic-field sensing applications is investigated by characterizing the dynamical magnetoelectric response of La doped (0.6)BiFeO₃-(0.4)PbTiO₃ piezoceramics. The results are compared with those obtained in Nb doped (1 wt. %) PbZr_0.53Ti_0.47O₃ (PZT-5A) piezoceramics and the observed non-linearity of the oscillating voltage response of (0.6)BiFeO₃-(0.4)PbTiO₃ piezoceramics is attributed to the overlapping of the intrinsic and extrinsic magnetoelectric effects that were successfully decoupled by analyzing the in-phase and out-of-phase voltage components relative to applied oscillatingmagnetic field. For an alternating cosine-like magnetic field of 0.32 Oe, at the piezoelectricresonance frequency (184.2 kHz), the alternating voltage response decreases from 7.77 mV, at −10 kOe, to 2.71 mV, at 1.8 kOe, to subsequently increases until 5.97 mV at 10 kOe. This non-linear voltage response, which can be easily converted into a linear signal by using the phase difference, can be used for static magnetic field sensing in a wide range of magnetic fields.

Link