Dynamic response of converse magnetoelectric effect in a PMN-PT-based multiferroic heterostructure

A multiferroic heterostructure, consisting of a 25 mu m thick MetglasA (R) ribbon affixed to a lead magnesium niobate-lead titanate (PMN-PT) crystal, was systemically studied to investigate the time response of converse magnetoelectric coupling under the application of electric fields at low frequencies (0.05 < f < 10 Hz). This multiferroic heterostructure exhibits a considerably strong converse magnetoelectric effect, CME=-80%, where CME=[M(E)-M(0)]/M(0), and a converse ME coupling constant, A=22.5 Oe-cm/kV, at frequencies below 1 Hz and near saturation electric polarization. A switching time (t (s)), representing the response time of the CME coupling, is measured to be 0.6 seconds for this heterostructure under the application of instantaneous electric fields. The switching time results in significant influences on the magnetoelectric effect especially at frequencies higher than 2 Hz. The dynamic response of CME coupling is predominantly determined by ferroelectric relaxation within the PMN-PT crystal, as opposed to the magnetic relaxation of the MetglasA (R) ribbon. A model was used to describe the dynamic behavior of CME coupling in disordered systems such as PMN-PT.