Holographic Magnetic Susceptibility

TL;DR

This paper investigates the analytic structure of holographic magnetic susceptibility in a strong-coupling regime using a Reissner-Nordström-AdS model, revealing unique branch-cut behaviors and their impact on Friedel-like oscillations.

Contribution

It analytically characterizes the complex momentum-plane structure of holographic magnetic susceptibility at zero temperature, highlighting differences from Fermi liquids.

Findings

Susceptibility remains analytic around the real axis at zero temperature.

Identified pairs of branch-cuts parallel to the imaginary axis at large Im(q).

Derived analytical expressions for susceptibility at large and small momenta.

Abstract

The (2+1)-dimensional static magnetic susceptibility in strong-coupling is studied via a Reissner-Nordstr\"{o}m-AdS geometry. The analyticity of the susceptibility on the complex momentum $\mathfrak{q}$-plane in relation to the Friedel-like oscillation in coordinate space is explored. In contrast to the branch-cuts crossing the real momentum-axis for a Fermi liquid, we prove that the holographic magnetic susceptibility remains an analytic function of the complex momentum around the real axis in the limit of zero temperature, At zero temperature, we located analytically two pairs of branch-cuts that are parallel to the imaginary momentum-axis for large $|\text{Im}\ \mathfrak{q}|$ but become warped with the end-points keeping away from the real and imaginary momentum-axes. We conclude that these branch-cuts give rise to the exponential decay behaviour of Friedel-like oscillation of magnetic susceptibility in coordinate space. We also derived the analytical forms of the susceptibility in large and small-momentum, respectively.