Controlling spin-polarized carriers at the SrTiO₃/EuO interface via the ferroelectric field effect

Using first principle calculations, we investigate the magneto-electric field effect at the SrTiO3/EuO interface in the BaTiO3/SrTiO3/EuO heterostructure. The spontaneous polarization in tetragonal BaTiO3 is demonstrated to control the movement of the two-dimensional electron gas in SrTiO3 across the interface with ferromagnetic EuO as well as induce spin polarized two-dimensional hole gas and influence the electronic structure at this interface. We also investigate the effect of oxygen vacancy in SrTiO3 near the SrTiO3/EuO interface. To investigate the ferroelectric polarization morphology, we use the phenomenological Landau-Khalatnikov model and compare it with the results of first principle calculations.
Reference: W. Li, L. Gao, and A. A. Demkov, “Controlling spin-polarized carriers at the SrTiO3/EuO interface via the ferroelectric field effect”, Phys. Rev. B 102, 035308 (2020).