Nature 525, 363–366 doi:10.1038/nature14881
With delicate crystal engineering of a perovskite oxide, traditionally impossible switching of polarization and magnetization at room temperature is now a reality. This kind of room temperature tuneable materials will open doors for the development of many new functional devices and products.
The search for room temperature magnetoelectric multiferroic materials, combining ferroelectricity and and ferromagnetism, is driven by a strong desire to fabricate novel functional devices. Ferroelectricity is the long-range order of atomic-scale electric dipoles that can be switched by an electric field, and ferromagnetism is long-range order of magnetic dipoles that can be switched by a magnetic field. Combining the two is problematical because of the opposing requirements for realizing these two properties. Mathew Rosseinsky and colleagues now show that ferroelectricity and ferromagnetism can be combined in a bulk perovskite oxide at room temperature by constructing a percolating network of interacting magnetic ions within a structural scaffold exhibiting polar lattice symmetries at a morphotropic phase boundary. This method should allow the generation of a range of tuneable multiferroic materials for possible practical applications.