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arXiv · 1912.01908

Parquet dual fermion approach for the Falicov-Kimball model

Katharina Astleithner·Anna Kauch·Tin Ribic·Karsten Held
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Abstract

In the Falicov-Kimball model, a model for (annealed) disorder, we expect weak localization corrections to the optical conductivity. However, we get such weak localization effects only when employing a pp-ladder approximation in the dual fermion approach. In the full parquet approach these pp-contributions are suppressed by ph-reducible diagrams. For the optical conductivity, we find that the pht-channel yields the main contribution, even in the region where weak localization in the pp-ladder was indicated.

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Katharina Astleithner, Anna Kauch, Tin Ribic, Karsten Held. 2019-12-04. Parquet dual fermion approach for the Falicov-Kimball model. https://doi.org/10.1103/physrevb.101.165101

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