Enhanced magnetoelectric effect in heterostructure of magnetostrictive alloy bars and piezoelectric single-crystal transformer

We report an enhanced magnetoelectric (ME) effect in a heterostructure consisting of a long-type, longitudinally-longitudinally polarized 0.71Pb(Mg1/3Nb2/3)O-3-0.29PbTiO(3) (PMN-PT) piezoelectric single-crystal transformer with its input part sandwiched between two longitudinally magnetized Tb0.3Dy0.7Fe1.92 (Terfenol-D) magnetostrictive alloy bars. The observed ME effect has two independent operational modes: namely, ME sensing mode and ME transduction mode. The ME sensing mode features a large ME voltage coefficient (alpha(V)) of similar to 0.32 V/Oe over a flat frequency range of 1-50 kHz, while the ME transduction mode possesses two colossal resonance alpha(V) of 7.6 and 7.9 V/Oe, corresponding to the first and second longitudinal resonances, at 56.2 and 127.9 kHz, respectively. This enhanced dual-mode ME effect not only enables the application potential of the heterostructure, but also advances the technology of power-free ME sensors and transducers. (C) 2011 American Institute of Physics. [doi:10.1063/1.3529439]