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arXiv · 1711.01127

Exploring excited eigenstates of many-body systems using the functional renormalization group

Christian Klöckner·Dante Marvin Kennes·Christoph Karrasch
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Abstract

We introduce approximate, functional renormalization group based schemes to obtain correlation functions in pure excited eigenstates of large fermionic many-body systems at arbitrary energies. The algorithms are thouroughly benchmarked and their strengths and shortcomings are documented using a one-dimensional interacting tight-binding chain as a prototypical testbed. We study two `toy applications' from the world of Luttinger liquid physics: the survival of power laws in lowly-excited states as well as the spectral function of high-energy `block' excitations which feature several single-particle Fermi edges.

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Christian Klöckner, Dante Marvin Kennes, Christoph Karrasch. 2018-04-10. Exploring excited eigenstates of many-body systems using the functional renormalization group. https://doi.org/10.1103/physrevb.97.195121

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