Towards a holographic marginal Fermi liquid

TL;DR

This paper introduces a class of 2+1D field theories coupled with semi-holographic fermions that display strange metallic behavior, supported by dual gravitational descriptions involving probe branes in specific AdS backgrounds.

Contribution

It constructs new holographic models of strange metals using lattice defect theories with supersymmetric Chern-Simons interactions and explores their gravitational duals.

Findings

Models exhibit strange metallic behavior in large N limit.

Dual descriptions involve probe M2 and D2 branes in AdS backgrounds.

Challenges include backreaction and radiative corrections at finite N.

Abstract

We present an infinite class of 2+1 dimensional field theories which, after coupling to semi-holographic fermions, exhibit strange metallic behavior in a suitable large $N$ limit. These theories describe lattices of hypermultiplet defects interacting with parity-preserving supersymmetric Chern-Simons theories with $U(N) \times U(N)$ gauge groups at levels $\pm k$. They have dual gravitational descriptions in terms of lattices of probe M2 branes in $AdS_4 \times S^7/Z_k$ (for $N \gg 1, N \gg k^5$) or probe D2 branes in $AdS_4 \times CP^3$ (for $N \gg k \gg 1, N \ll k^5$). We discuss several challenges one faces in maintaining the success of these models at finite $N$, including backreaction of the probes in the gravity solutions and radiative corrections in the weakly coupled field theory limit.