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arXiv · 2204.06426

Multi-band D-TRILEX approach to materials with strong electronic correlations

Matteo Vandelli·Josef Kaufmann·Mohammed El-Nabulsi·Viktor Harkov·Alexander I. Lichtenstein·Evgeny A. Stepanov
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Abstract

We present the multi-band dual triply irreducible local expansion (D-TRILEX) approach to interacting electronic systems and discuss its numerical implementation. This method is designed for a self-consistent description of multi-orbital systems that can also have several atoms in the unit cell. The current implementation of the D-TRILEX approach is able to account for the frequency- and channel-dependent long-ranged electronic interactions. We show that our method is accurate when applied to small multi-band systems such as the Hubbard-Kanamori dimer. Calculations for the extended Hubbard, the two-orbital Hubbard-Kanamori, and the bilayer Hubbard models are also discussed.

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Matteo Vandelli, Josef Kaufmann, Mohammed El-Nabulsi, Viktor Harkov, Alexander I. Lichtenstein, Evgeny A. Stepanov. 2022-04-13. Multi-band D-TRILEX approach to materials with strong electronic correlations. https://doi.org/10.21468/scipostphys.13.2.036

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