Doping-dependent bandwidth renormalization and spin-orbit coupling in (Sr1-xLax)(2)RhO4

Abstract

We investigate the electronic structure of (Sr1-xLax)(2)RhO4 using a combination of the density functional and dynamical mean-field theories. Unlike the earlier local density approximation plus Hubbard U (LDA+U) studies, we find no sizable enhancement of the spin-orbit splitting due to electronic correlations and show that such an enhancement is a spurious effect of the static mean-field approximation of the LDA+U method. The electron doping suppresses the importance of electronic correlations, which is reflected in the quasi-particle bandwidth increasing with x. (Sr1-xLax)(2)RhO4 can be classified as a weakly correlated metal, which becomes an itinerant in-plane ferromagnet (but possibly A-type antiferromagnet) due to Stoner instability around x = 0.2.