Shear-mode magnetostrictive/piezoelectric composite with an enhanced magnetoelectric coefficient

摘要

A magnetoelectric (ME) laminate heterostructure consisting of two shear-mode piezoelectric Pb(Mg_(1/3)Nb_(2/3))O_3-30PbTiO_3 (PMN-PT) single crystal layers, a longitudinally magnetized magnetostrictive Tb_(0.3)Dy_(0.7)Fe_(1.92) alloy plate, and a mechanical clamping brass substrate has been demonstrated that has a notably superior ME effect relative to previous laminate configurations of these two materials. A giant ME coefficient of 7.5 V/(cm Oe) at low frequencies under an optimal dc magnetic bias of ~400 Oe was found. The superior ME effects originate from the nature of heterostructure design, which allows the PMN-PT single crystals to operate in a shear mode that has maximum electro-mechanical coupling (i.e., d_(15) = 6800 pC/N).