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We investigate the antiferromagnetic insulating state of the recently discovered double perovskites Sr$_2$XOsO$_6$ (X$=$Sc, 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 Sr$_2$XOsO$_6$ (X$=$Sc, Mg) induce band narrowing effects which enhance local electronic correlations. The half-filled $5d^3$ orbitals of Os in Sr$_2$ScOsO$_6$ fall into a magnetically ordered correlated regime, which is slightly affected and reduced by the spin-orbit coupling. The electronic configuration $5d^2$ of Os in Sr$_2$MgOsO$_6$ responses differently to electronic correlations promoting a less localized state than Sr$_2$ScOsO$_6$ at the same strength of electronic interactions. We find that the inclusion of spin-orbit coupling drives Sr$_2$MgOsO$_6$ 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 Sr$_2$XOsO$_6$ (X$=$Sc, Mg).
We have studied Ir spin and orbital magnetic moments in the double perovskites La$_{2-x}$Sr$_x$CoIrO$_6$ by x-ray magnetic circular dichroism. In La$_2$CoIrO$_6$, Ir$^{4+}$ couples antiferromagnetically to the weak ferromagnetic moment of the canted
The magnetism of the double perovskite compounds SLFCOx ($x$ = 0, 1, 2) are contrasted using magnetization, neutron diffraction and electron paramagnetic resonance with the support from density functional theory calculations. LFCO is identified as a
Double-perovskite oxides that contain both 3d and 5d transition metal elements have attracted growing interest as they provide a model system to study the interplay of strong electron interaction and large spin-orbit coupling (SOC). Here, we report o
Sr$_{3}$ZnIrO$_{6}$ is an effective spin one-half Mott insulating iridate belonging to a family of magnets which includes a number of quasi-one dimensional systems as well as materials exhibiting three dimensional order. Here we present the results o
The Fe electronic structure and magnetism in (i) monoclinic Ca$_2$FeReO$_6$ with a metal-insulator transition at $T_{MI} sim 140$ K and (ii) quasi-cubic half-metallic Ba$_2$FeReO$_6$ ceramic double perovskites are probed by soft x-ray absorption spec