Friedel Oscillations in Holographic Metals

TL;DR

This paper investigates the conditions for Friedel oscillations in holographic metals, revealing that certain geometries show clear oscillations while others do not, providing insights into boundary fermionic states.

Contribution

It identifies specific holographic geometries where Friedel oscillations occur and distinguishes cases where they are suppressed, advancing understanding of boundary fermionic behavior.

Findings

Friedel oscillations appear in hard wall AdS geometries.

Oscillations are suppressed in electron star geometries.

Provides a new way to characterize boundary states in holography.

Abstract

In this article we study the conditions under which holographic metallic states display Friedel oscillations. We focus on systems where the bulk charge density is not hidden behind a black hole horizon. Understanding holographic Friedel oscillations gives a clean way to characterize the boundary system, complementary to probe fermion calculations. We find that fermions in a "hard wall" AdS geometry unambiguously display Friedel oscillations. However, similar oscillations are washed out for electron stars, suggesting a smeared continuum of Fermi surfaces.