Correlation-induced phase transitions in (111) bilayers of perovskite transition-metal oxides

We investigate the correlation-induced Mott, magnetic and topological phase transitions in (111) bilayers of perovskite transition-metal oxides LaAuO$_3$ and SrIrO$_3$ for which the previous density functional theory (DFT) calculations predicted topological insulating states. Using the dynamical-mean-field theory with DFT band structure and realistic Coulomb interactions, LaAuO$_3$ bilayer is shown to be far away from a Mott insulating regime, and a topological-insulating state is robust. On the other hand, SrIrO$_3$ bilayer is on the verge of an orbital-selective topological Mott transition. We also study the effect of magnetism in these systems.