Interfacial Effect Enhanced Electric Field Control of the Magnetism in Pt/Fe/PMN-PT Heterostructures

The strain and charge comediated magnetoelectric coupling effect has been investigated in the Pt/Fe/0.7Pb-(Mg1/3Nb2/3)O-3-0.3PbTiO(3) (PMN-PT) heterostructures. An oxidized interfacial layer FeOx is formed at the Fe/PMN-PT interface, which assists in realizing the multistate magnetization by the electric field. The remnant magnetization variation under the positive polarization reaches similar to 120% in the (011) Pt/Fe(2 nm)/PMN-PT heterostructure along the in-plane [01-1] direction, which is larger than that (similar to 67% and similar to 1.8%) of the Pt/Fe/PMN-PT heterostructures with 5 and 11 nm Fe films. The enhanced electric field manipulation of magnetization variation as the thickness of the Fe film decreases indicates an interfacial dominant magnetoelectric coupling effect. Moreover, the asymmetrical magnetization variation under the positive and negative electric fields originates from the ferroelectric polarization induced carrier density change and redox-oxidation reactions based on the strain effect at the interfacial FeOx layer. It has great potential for application in magnetoelectric information storage devices of the Pt/Fe/PMN-PT heterostructures.