Hidemaro Suwa

Abstract We investigate an experimental toy-model system of a pseudospin-half square-lattice Hubbard Hamiltonian in [(SrIrO3)1/(CaTiO3)1] to include both nontrivial complex hopping and moderate electron correlation. While the former induces electronic Berry phases as anticipated from the weak-coupling limit, the latter stabilizes an antiferromagnetic Mott insulator ground state analogous to the strong-coupling limit.

Density functional theory (DFT) calculations were performed using projector-augmented wave method with the generalized gradient approximation (GGA)34 as implemented in the Vienna ab-initio Simulation Package35. The plane wave cutoff was chosen as 500 eV on the basis of the convergence tests. To model the epitaxial relationship of samples grown on a SrTiO substrate, the in-plane lattice parameters were fixed to the substrate value, 3.905 Å.