Magnetic Properties of LaAlO3/SrTiO3 Heterostructure Modelled on a Supercomputer

Abstract

The oxide heterostructure composed of LaAlO3 (LAO) thin film on top of SrTiO3 (STO) substrate is the best known example of a system where a metallic state is formed in the STO layers next to the interface [1]. In the frame of present work we analyze an impact of oxygen vacancies and hydrogen dopants located in the AlO2 surface layer and in the TiO2 interfacial plane of LAO/STO heterostructure onto the magnetic properties by performing spin-polarized calculations based on density functional theory (DFT). We found stable local magnetic moments formed within atomically thin magnetic layers at the interface. We confirmed that magnetism can be generated by oxygen vacancies located either at the surface or at the interface. In addition, we demonstrate magnetic moments formation by hydrogen dopants located at the interface. Finally, the case of two defects combination was investigated, when negligibly small magnetic moment induction was found to take place.