Self-consistency over the charge-density in dynamical mean-field theory: a linear muffin-tin implementation and some physical implications

摘要

We present a simple implementation of the dynamical mean-field theoryapproach to the electronic structure of strongly correlated materials. Thisimplementation achieves full self-consistency over the charge density, takinginto account correlation-induced changes to the total charge density andeffective Kohn-Sham Hamiltonian. A linear muffin-tin orbital basis-set is used,and the charge density is computed from moments of the many bodymomentum-distribution matrix. The calculation of the total energy is alsoconsidered, with a proper treatment of high-frequency tails of the Green'sfunction and self-energy. The method is illustrated on two materials withwell-localized 4f electrons, insulating cerium sesquioxide Ce2O3 and thegamma-phase of metallic cerium, using the Hubbard-I approximation to thedynamical mean-field self-energy. The momentum-integrated spectral function andmomentum-resolved dispersion of the Hubbard bands are calculated, as well asthe volume-dependence of the total energy. We show that full self-consistencyover the charge density, taking into account its modification by strongcorrelations, can be important for the computation of both thermodynamical andspectral properties, particularly in the case of the oxide material.