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arXiv · 1307.0004

Non-Fermi liquid fixed point in a Wilsonian theory of quantum critical metals

A. Liam Fitzpatrick·Shamit Kachru·Jared Kaplan·S. Raghu
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Abstract

We study the problem of disorder-free metals near a continuous quantum critical point. We depart from the standard paradigm of Hertz and Millis, and treat both fermions and bosons i.e. order parameter fields) on equal footing. We construct a Wilsonian effective field theory that integrates out only high energy boson and fermion modes. Below the upper critical dimension of the theory (d=3 spatial dimensions), we find new fixed points in which the bosons are described by the Wilson-Fisher fixed point and are coupled to a non-Fermi liquid metal. We describe subtleties with the renormalization group flow of four-Fermi interactions, which can be surmounted in a controlled large N limit. In this limit, we find that the theory has no superconducting instability.

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A. Liam Fitzpatrick, Shamit Kachru, Jared Kaplan, S. Raghu. 2013-06-28. Non-Fermi liquid fixed point in a Wilsonian theory of quantum critical metals. https://doi.org/10.1103/physrevb.88.125116

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