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Gauge invariant response functions in Algebraic Fermi liquids

M. Franz·T. Pereg-Barnea·D. E. Sheehy·Z. Tesanovic
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Abstract

A new method is developed that permits the 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 theory of cuprate superconductors. The staggered spin susceptibility is found to exhibit a characteristic anomalous dimension exponent η_4, while other correlators show behavior consistent with the conservation laws imposed by the symmetries of the underlying theory.

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M. Franz, T. Pereg-Barnea, D. E. Sheehy, Z. Tesanovic. 2003-07-31. Gauge invariant response functions in Algebraic Fermi liquids. https://doi.org/10.1103/physrevb.68.024508

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