Circumferential-mode, quasi-ring-type, manetoelectric laminate composite - a highly sensitive electric current and/or vortex magnetic field sensor

A quasi-ring-type magnetoelectric (ME) laminate composite consisting of a circumferentially poled piezoelectric Pb(Zn1/3Nb2/3O)(3-)4.5 at.% PbTiO(3)single-crystal ring and two circumferentially magnetized magnetostrictive TERFENOL-D rings was fabricated and found to have a giant ME voltage coefficient of 2.2 V/Oe, or equivalently a ME field coefficient of 5.5 V/cm Oe, over the frequency range of 0.5 < f < 10(5) Hz. This circumferential-mode quasiring ME laminate can detect ac currents (noncontact) as small as 10(-7) A, and/or a vortex magnetic field as small as 6 x 10(-12) Tesla. In addition, we demonstrated current sensing capability of the quasiring laminate in a power electronics module. (c) 2005 American Institute of Physics.