Interface-induced magnetic polar metal phase in complex oxides.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 31748526.
- Also identified by DOI 10.1038/s41467-019-13270-7 and PMC identifier 6868157.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Polar metals are commonly defined as metals with polar structural distortions. Strict symmetry restrictions make them an extremely rare breed as the structural constraints favor insulating over metallic phase. Moreover, no polar metals are known to be magnetic. Here we report on the realization of a magnetic polar metal phase in a BaTiO<sub>3</sub>/SrRuO<sub>3</sub>/BaTiO<sub>3</sub> heterostructure. Electron microscopy reveals polar lattice distortions in three-unit-cells thick SrRuO<sub>3</sub> between BaTiO<sub>3</sub> layers. Electrical transport and magnetization measurements reveal that this heterostructure possesses a metallic phase with high conductivity and ferromagnetic ordering with high saturation moment. The high conductivity in the SrRuO<sub>3</sub> layer can be attributed to the effect of electrostatic carrier accumulation induced by the BaTiO<sub>3</sub> layers. Density-functional-theory calculations provide insights into the origin of the observed properties of the thin SrRuO<sub>3</sub> film. The present results pave a way to design materials with desired functionalities at oxide interfaces.