High-spin to low-spin and orbital polarization transitions in multiorbital Mott systems
Abstract
We study the interplay of crystal field splitting and Hund coupling in a two-orbital model which captures the essential physics of systems with two holes in the e_g shell such as LaNiO_3 or La_2NiO_4. We use single site dynamical mean field theory with a newly developed impurity solver which is able to access strong couplings and low temperatures. The fillings of the orbitals and the location of phase boundaries are computed as a function of Coulomb repulsion, exchange coupling and crystal field splitting. We find that the Hund coupling can drive the system into a novel Mott insulating phase with vanishing orbital susceptibility. Away from half-filling, a change in crystal field splitting can induce an orbital selective Mott transition.Keywords
All Related Versions
This publication has 0 references indexed in Scilit: