Significant enhancement of magnetoelectric output in multiferroic heterostructural films modulated by electric polarization cycles

The Pb(Zr,Ti)O3/CoFe2O4/Pb(Zr,Ti)O3 heterostructural film was prepared and the variation in its magnetoelectric output with the cycling electric polarization was investigated. The giant magnetoelectric output, which was about one order enhancement in magnitude compared with the original film, was observed after the film was subjected to the cycling electric polarization with the strength of 45 MV/m and cycling number of ∼2.2×108. We consider that both oxygen vacancy migration in the heterostructure and the polarized electric charges in the CoFe2O4 layer play important roles in such significant magnetoelectric enhancement.