The influence of Coulomb Correlations and Spin-Orbit Coupling in the electronic structure of double perovskites SrXOsO (XSc, Mg)
arXiv:1611.06482
Abstract
We investigate the antiferromagnetic insulating state of the recently discovered double perovskites SrXOsO (XSc, Mg) by using ab-initio calculations (based on Density Functional Theory and Dynamical Mean-Field Theory) to elucidate the interplay between electronic correlations and spin-orbit coupling. The structural details of SrXOsO (XSc, Mg) induce band narrowing effects which enhance local electronic correlations. The half-filled orbitals of Os in SrScOsO fall into a magnetically ordered correlated regime, which is slightly affected and reduced by the spin-orbit coupling. The electronic configuration of Os in SrMgOsO responses differently to electronic correlations promoting a less localized state than SrScOsO at the same strength of electronic interactions. We find that the inclusion of spin-orbit coupling drives SrMgOsO toward insulating behaviour and promotes a large tendency in formation of orbital magnetization antiparallel to the spin moment. The formation of the AFM state is linked to the evidence of correlated Hubbard bands in the paramagnetic solution of SrXOsO (XSc, Mg).