Spin and charge order in doped spin-orbit coupled Mott insulators

Abstract

We study a two-dimensional single band Hubbard Hamiltonian with antisymmetric spin-orbit coupling. We argue that this is the minimal model to understand the electronic properties of locally non-centrosymmetric transition-metal (TM) oxides such as Sr2IrO4. Based on exact diagonalizations of small clusters and the random phase approximation, we investigate the correlation effects on charge and magnetic order as a function of doping and of the TM-oxygen-TM bond angle θ. For small doping and θ 15 • we find dominant commensurate inplane antiferromagnetic fluctuations while ferromagnetic fluctuations dominate for θ 25 • . Moderately strong nearest-neighbor Hubbard interactions can also stabilize a charge density wave order. Furthermore, we compare the dispersion of magnetic excitations for the hole-doped case to resonant inelastic X-ray scattering data and find good qualitative agreement.

Topological Superconductivity in Sn/Si(111) driven by non-local Coulomb interactions

“…In the framework of linear response theory and using the Kubo formula, the spatial components of the bare susceptibility at temperature T are given by [25]…”