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Landau's quasi-particle mapping: Fermi liquid approach and Luttinger liquid behavior

Caspar P. Heidbrink·Götz S. Uhrig
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Abstract

A continuous unitary transformation is introduced which realizes Landau's mapping of the elementary excitations (quasi-particles) of an interacting Fermi liquid system to those of the system without interaction. The conservation of the number of quasi-particles is important. The transformation is performed numerically for a one-dimensional system, i.e. the worst case for a Fermi liquid approach. Yet evidence for Luttinger liquid behavior is found. Such an approach may open a route to a unified description of Fermi and Luttinger liquids on all energy scales.

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Caspar P. Heidbrink, Götz S. Uhrig. 2002-03-13. Landau's quasi-particle mapping: Fermi liquid approach and Luttinger liquid behavior. https://doi.org/10.1103/physrevlett.88.146401

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