A multi-functional magnetoelectric sensor based on eddy current in cantilevered piezoelectric unimorph bender

This paper reports on a multi-functional magnetoelectric (ME) sensor which was made up of a wire carrying ac current and cantilevered piezoelectric unimorph bender consisting of a single piezoelectric layer bonded to an alumina plate. The vortex magnetic field induced by ac current generates eddy currents within the electrodes and consequently Lorentz forces. Thanks to the coupling of the piezoelectric layer and Lorentz forces in the metal electrodes, transverse strain leading to bender´s deformation and direct magnetoelectric response appeared when ac magnetic flux was across the thickness direction of unimorph bender. Thus, the magnetoelectric voltage of unimorph bender can be controlled by adjusting ac current in the conductor. Consequently, room temperature ac/dc magnetic field detection is achievable using this two layer piezoelectric unimorph bender with a good sensitivity and linear response versus dc/ac magnetic field change.