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arXiv · 1312.1519

Linear response within the projection-based renormalization method: Many-body corrections beyond the random phase approximation

Van-Nham Phan·Klaus W. Becker·Holger Fehske
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Abstract

The explicit evaluation of linear response coefficients for interacting many-particle systems still poses a considerable challenge to theoreticians. In this work we use a novel many-particle renormalization technique, the so-called projector-based renormalization method, to show how such coefficients can systematically be evaluated. To demonstrate the prospects and power of our approach we consider the dynamical wave-vector dependent spin susceptibility of the two-dimensional Hubbard model and also determine the subsequent magnetic phase diagram close to half-filling. We show that the superior treatment of (Coulomb) correlation and fluctuation effects within the projector-based renormalization method significantly improves the standard random phase approximation results.

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Van-Nham Phan, Klaus W. Becker, Holger Fehske. 2014-03-11. Linear response within the projection-based renormalization method: Many-body corrections beyond the random phase approximation. https://doi.org/10.1140/epjb%2Fe2014-50028-2

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