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arXiv · 1711.04338

A Framework for Studying a Quantum Critical Metal in the Limit $N_f\rightarrow0$

Petter Säterskog
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Abstract

We study a model in 1+2 dimensions composed of a spherical Fermi surface of $N_f$ flavors of fermions coupled to a massless scalar. We present a framework to non-perturbatively calculate general fermion $n$-point functions of this theory in the limit $N_f\rightarrow0$ followed by $k_F\rightarrow\infty$ where $k_F$ sets both the size and curvature of the Fermi surface. Using this framework we calculate the zero-temperature fermion density-density correlation function in real space and find an exponential decay of Friedel oscillations.

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Petter Säterskog. 2017-11-12. A Framework for Studying a Quantum Critical Metal in the Limit $N_f\rightarrow0$. https://doi.org/10.21468/scipostphys.4.3.015

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