Interaction flow method reloaded

Daniel Rohe

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arXiv · 2201.04823

Interaction flow method reloaded

Daniel Rohe

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Abstract

A recently proposed extension of the interaction flow method is applied to exemplary cases of selected physical and methodical parameters for the two-dimensional Hubbard model away from half-filling and perfect nesting. In this scheme, the self-energy is calculated on the real-frequency axis and its feedback on the flow of interactions is included in a simple manner via a momentum-dependent quasi-particle weight. Results for two different types of self-energy feedback are compared to the case without feedback and to existing results stemming from calculations for imaginary frequencies. Various physical and non-physical aspects which influence the outcome qualitatively and quantitatively are addressed. Some tentative directions for future developments are suggested.

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Daniel Rohe. 2022-01-13. Interaction flow method reloaded. https://arxiv.org/abs/2201.04823

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