Holographic Charge Oscillations

TL;DR

This paper investigates charge density oscillations induced by impurities in a holographic black hole system, revealing temperature-dependent behaviors that resemble Friedel oscillations in Fermi liquids.

Contribution

It demonstrates how charge oscillations in a holographic model transition from exponential damping at zero temperature to Friedel-like oscillations at finite temperature.

Findings

Oscillations linked to singularities in correlation functions.

At finite temperature, oscillations resemble Friedel oscillations.

Zero temperature oscillations remain exponentially damped.

Abstract

The Reissner-Nordstrom black hole provides the prototypical description of a holographic system at finite density. We study the response of this system to the presence of a local, charged impurity. Below a critical temperature, the induced charge density, which screens the impurity, exhibits oscillations. These oscillations can be traced to the singularities in the density-density correlation function moving in the complex momentum plane. At finite temperature, the oscillations are very similar to the Friedel oscillations seen in Fermi liquids. However, at zero temperature the oscillations in the black hole background remain exponentially damped, while Friedel oscillations relax to a power-law