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arXiv:cond-mat/0211119 · Physical review. B, Condensed matter

Gauge-invariant response functions in algebraic Fermi liquids

Marcel Franz, T. Pereg-Barnea, Daniel E. Sheehy, Zlatko Tešanović

Published Jul 18, 2003• 38 citations
arXivHTMLPDF

Abstract

A method is developed that permits a simple evaluation of two-loop response functions for fermions coupled to a gauge field. We employ this method to study the gauge-invariant response functions in the algebraic Fermi liquid, a non-Fermi liquid state proposed to describe the pseudogap phase in the ${\mathrm{QED}}_{3}$ theory of cuprate superconductors. The staggered spin susceptibility is found to exhibit a characteristic anomalous dimension exponent ${\ensuremath{\eta}}_{4},$ while other correlators show a behavior consistent with the conservation laws imposed by the symmetries of the underlying theory.

DOI
10.1103/physrevb.68.024508

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A method is developed that permits a simple evaluation of two-loop response functions for fermions coupled to a gauge field. We employ this method to study the gauge-invariant response functions in the algebraic Fermi liquid, a non-Fermi liquid state proposed to describe the pseudogap phase in the QED3{\mathrm{QED}}_{3}QED3​ theory of cuprate superconductors. The staggered spin susceptibility is found to exhibit a characteristic anomalous dimension exponent \ensuremathη4,{\ensuremath{\eta}}_{4},\ensuremathη4​, while other correlators show a behavior consistent with the conservation laws imposed by the symmetries of the underlying theory.
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