Interface effects at a ferromagnetic and ferroelectric junction

• FeSi/TiO2, FeFe/TiO2 and SiSi/TiO2 interfaces are more stable than Fe/TiO2 interface.
• Paraelectric phase is recovered in BaTiO3 slab for SiSi/TiO2 interface.
• More magnetizations are achieved at FeFe/TiO2 interface.
• Magnetoelectric effect is induced by hybridization between Fe2-d and Ti-d.

Magnetoelectric effect at Fe3Si/BaTiO3 (001) interfaces is investigated by using the first-principles calculations. Interfacial separation works reveal that the FeSi/TiO2 and modified FeFe/TiO2 and SiSi/TiO2 interfaces are more stable than the Fe/TiO2 interface. While for the modified SiSi/TiO2 interface, the paraelectric phase is recovered in BaTiO3 slab due to its symmetrical structure in the central TiO2 layer. Compared with the original Fe/TiO2 and FeSi/TiO2 interfaces, more net change magnetizations are achieved at modified FeFe/TiO2 interface. The predicted magnetoelectric effect opens a direction to control magnetic properties of thin-film layered structure by electric fields.