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arXiv · 1102.2858

Extremely Correlated Fermi Liquids

B. Sriram Shastry
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Abstract

We present the theory of an extremely correlated Fermi liquid (ECFL) with $U\to \infty$. This liquid has an underlying Fermi liquid (FL) Greens function that is further caparisoned. The theory leads to two parallel hierarchies of equations that permit iterative approximations in a certain parameter. Preliminary results for the spectral functions display a broad background and a distinct $T$ dependent left skew. An important energy scale $Δ(\vec{k},x)$ emerges as the average inelasticity of the FL Greens function, and influences the photoemission spectra profoundly. A duality is identified wherein an apparent loss of coherence of the ECFL results from an excessively sharp FL.

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B. Sriram Shastry. 2011-08-08. Extremely Correlated Fermi Liquids. https://doi.org/10.1103/physrevlett.107.056403

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