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arXiv · 1903.04984

Density Functional Theory of the Hubbard-Holstein Model

E. Viñas Boström·P. Helmer·P. Werner·C. Verdozzi
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Abstract

We present a density functional theory (DFT) for lattice models with local electron-electron (e-e) and electron-phonon (e-ph) interactions. Exchange-correlation potentials are derived via dynamical mean field theory for the infinite-dimensional Bethe lattice, and analytically for an isolated Hubbard-Holstein site. These potentials exhibit discontinuities as a function of the density, which depend on the relative strength of the e-e and e-ph interactions. By comparing to exact benchmarks, we show that the DFT formalism gives a good description of the linear conductance and real-time dynamics.

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E. Viñas Boström, P. Helmer, P. Werner, C. Verdozzi. 2019-03-12. Density Functional Theory of the Hubbard-Holstein Model. https://doi.org/10.1103/physrevresearch.1.013017

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