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, (Tb(1-x)Dy(x)Fe(2-y)) and piezoelectric Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3), has been developed. Our MLC magnetoelectric sensor presently shows a limit in (i) working frequency of similar to 5 x 10(-3) Hz; and (ii) magnetic field sensitivity of 10(-7), 10(-9), and 10(-11) T for frequencies of f = 10(-2), 1, and 10(2) Hz, respectively. The results open up possibilities for sensitive low frequency passive magnetic anomaly detection. (c) 2005 American Institute of Physics.