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arXiv · 1809.07719

Model Hamiltonian for strongly-correlated systems: Systematic, self-consistent, and unique construction

Ryan Requist·E. K. U. Gross
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Abstract

An interacting lattice model describing the subspace spanned by a set of strongly-correlated bands is rigorously coupled to density functional theory to enable ab initio calculations of geometric and topological material properties. The strongly-correlated subspace is identified from the occupation number band structure as opposed to a mean-field energy band structure. The self-consistent solution of the many-body model Hamiltonian and a generalized Kohn-Sham equation exactly incorporates momentum-dependent and crystal-symmetric correlations into electronic structure calculations in a way that does not rely on a separation of energy scales. Calculations for a multiorbital Hubbard model demonstrate that the theory accurately reproduces the many-body polarization.

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Ryan Requist, E. K. U. Gross. 2018-09-20. Model Hamiltonian for strongly-correlated systems: Systematic, self-consistent, and unique construction. https://doi.org/10.1103/physrevb.99.125114

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