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arXiv · 2010.03938

Self-consistent ladder D$Γ$A approach

Josef Kaufmann·Christian Eckhardt·Matthias Pickem·Motoharu Kitatani·Anna Kauch·Karsten Held
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Abstract

We present and implement a self-consistent D$Γ$A approach for multi-orbital models and ab initio materials calculations. It is applied to the one-band Hubbard model at various interaction strengths with and without doping, to the two-band Hubbard model with two largely different bandwidths, and to SrVO$_3$. The self-energy feedback reduces critical temperatures compared to dynamical mean-field theory, even to zero temperature in two-dimensions. Compared to a one-shot, non-self-consistent calculation the non-local correlations are significantly reduced when they are strong. In case non-local correlations are weak to moderate as for SrVO$_3$, one-shot calculations are sufficient.

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Josef Kaufmann, Christian Eckhardt, Matthias Pickem, Motoharu Kitatani, Anna Kauch, Karsten Held. 2020-12-30. Self-consistent ladder D$Γ$A approach. https://doi.org/10.1103/physrevb.103.035120

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