Extremely low frequency response of magnetoelectric multilayer composites

A promising generation of extremely low frequency magnetic field sensors, based on multilayer composites (MLCs) of magnetostrictive Terfenol-D (Tb1−xDyxFe2−y) and piezoelectric Pb(Mg1∕3Nb2∕3)O3–PbTiO3, has been developed. Our MLC magnetoelectric sensor presently shows a limit in (i) working frequency of ∼5×10−3Hz; and (ii) magnetic field sensitivity of 10−7,10−9, and 10−11T for frequencies of f=10−2, 1, and 102Hz, respectively. The results open up possibilities for sensitive low frequency passive magnetic anomaly detection.