Abstract
Electric-field control of magnetism has recently received much attention because of low-power consumption, which has potential applications in low-power multifunction devices. Ferromagnetic/ferroelectric multiferroic heterostructure is a useful way to realize the electric-field control of magnetism. Strain-mediated magnetoelectric coupling with large magnetoelectric coupling coefficient at room temperature is one of the current research hotspot. In this paper, we give an overview of recent progress of strain-mediated magnetoelectric coupling in multiferroic heterostructures. This review paper consists of five parts: introduction of multiferroics, electric-field control of magnetism in multiferroic heterostructures, electrical control of magnetization reversal, electric-field control of magnetic tunnel junctions, and the future prospects of multiferroic heterostructures.
The basic concepts of multiferroics and background of magnetoelectric coupling effect are introduced in the first part.
In the second part, a brief review of the recent work on the Pb(Mg1/3Nb2/3)(0.7)Ti0.3O3 (PMN-PT) based multiferroic heterostructures is given. The PMN-PT has a FE domain structure, which plays a vital role in electric-field control of magnetism, especially the 109 degrees domain switching. For PMN-PT (001), the importance of 109 degrees domain switching on the nonvolatile electrical control of magnetism is discussed. For PMN-PT (011), it is shown how to obtain nonvolatile strain which induces magnetic easy axis to be rotated by 90 degrees. The work on electric-field modulation of ferromagnetic material with perpendicular magnetic anisotropy is also mentioned.
Electric-field control of magnetization reversal is still a challenge and remains elusive. Combination of strainmediated magnetoelectric coupling and exchanging bias is a promising method to reverse magnetization by electric field, and the exchange-biased system/ferroelectric structures are given in the third part. There are also some theoretical attempts and proposals to realize the electrical control of 180 degrees magnetization reversal. Then the method to manipulate magnetic tunnel junctions by electric field is given through integrating multiferroics and spintronics. Further outlook of the multiferroic heterostructures is also presented finally.