Fluctuations of a holographic quantum Hall fluid

TL;DR

This paper investigates the neutral excitation spectrum of a holographic quantum Hall fluid, revealing stable, gapped states with magneto-roton excitations caused by level crossings, enhancing understanding of quantum Hall phenomena via holography.

Contribution

It provides a detailed analysis of the neutral spectrum in the D2-D8' holographic model, identifying magneto-rotons and their origin from mode crossings, which is a novel insight.

Findings

The system is stable and gapped.

Magneto-rotons are present in the lowest and higher modes.

Magneto-rotons arise from level crossings between vector and scalar modes.

Abstract

We analyze the neutral spectrum of the holographic quantum Hall fluid described by the D2-D8' model. As expected for a quantum Hall state, we find the system to be stable and gapped and that, at least over much of the parameter space, the lowest excitation mode is a magneto-roton. In addition, we find magneto-rotons in higher modes as well. We show that these magneto-rotons are direct consequences of level crossings between vector and scalar modes.