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arXiv · 1402.5413

Slow Fermions in Quantum Critical Metals

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

We study the low-energy behavior of metals coupled to gapless bosons. This problem arises in several contexts in modern condensed matter physics; we focus on the theory of metals near continuous quantum phase transitions (where the boson is the order parameter). In the vicinity of d=3 spatial dimensions, the upper critical dimension of the theory, the ratio of fermion and boson speeds, v/c, acts as an additional control parameter, enabling us to access IR fixed points where this ratio vanishes. This limit corresponds to a non-Fermi liquid coupled to bosons with critical exponents governed by the Wilson-Fisher fixed point.

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A. Liam Fitzpatrick, Shamit Kachru, Jared Kaplan, Steven A. Kivelson, S. Raghu. 2014-02-21. Slow Fermions in Quantum Critical Metals. https://arxiv.org/abs/1402.5413

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