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arXiv · 2011.08780

Second-order dual fermion for multi-orbital systems

Erik G. C. P. van Loon
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Abstract

In dynamical mean-field theory, the correlations between electrons are assumed to be purely local. The dual fermion approach provides a systematic way of adding non-local corrections to the dynamical mean-field theory starting point. Initial applications of this method were largely restricted to the single-orbital Hubbard model. Here, we present an implementation of second-order dual fermion for general multi-orbital systems and use this approach to investigate spatial correlations in SrVO$_3$. In addition, the approach is benchmarked in several exactly solvable small systems.

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Erik G. C. P. van Loon. 2020-11-17. Second-order dual fermion for multi-orbital systems. https://doi.org/10.1088/1361-648x/abd9ed

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