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arXiv · 2212.11877

Non-linear responses and three-particle correlators in correlated electron systems exemplified by the Anderson impurity model

Patrick Kappl·Friedrich Krien·Clemens Watzenböck·Karsten Held
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Abstract

Three-particle correlators are relevant for, among others, Raman, Hall and non-linear responses. They are also required for the next order of approximations extending dynamical mean-field theory diagrammatically. We present a general formalism on how to treat these three-particle correlators and susceptibilities, and calculate the local three-particle response of the Anderson impurity model numerically. We find that genuine three-particle vertex corrections are sizable. In particular, it is not sufficient to just take the bare bubble terms or corrections based on the two-particle vertex. The full three-particle vertex must be considered.

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Patrick Kappl, Friedrich Krien, Clemens Watzenböck, Karsten Held. 2022-12-22. Non-linear responses and three-particle correlators in correlated electron systems exemplified by the Anderson impurity model. https://doi.org/10.1103/physrevb.107.205108

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