Interface Magnetoelectric Effects and Ferroelectric Tunnel Junctions

E. Y. Tsymbal

Department of Physics and Astronomy, University of Nebraska, Lincoln, NE 68588, USA

Multiferroic materials have recently attracted significant interest due to the coupling between different order parameters that can lead to new functionalities. One of the promising ways to achieve a strong coupling is to use heterogeneous interfaces, producing lattice strain, chemical bonding, and charge transfer effects, not existing in the bulk phase. For example, magnetoelectric effects may strongly be enhanced at the ferromagnetic/ferroelectric interfaces where the influence of ferroelectric displacements on the interface electronic structure may lead to a change in the magnetic moment and magnetic anisotropy. Ferromagnet/ferroelectric interfaces are also promising for application in ferroelectric tunnel junctions where a thin-film ferroelectric is used as a barrier layer. In these junctions, ferroelectric polarization reversal may lead to a sizable change in the conductance and the spin polarization. This talk will address our recent progress in the theoretical studies of these multiferroic interfaces and tunnel junctions which are interesting for application in multifunctional electronic devices.