Magneto-roton excitation of fractional quantum Hall effect: Comparison between theory and experiment

TL;DR

This paper compares theoretical calculations and experimental measurements of neutral magneto-roton excitations in the fractional quantum Hall effect, showing good agreement and overcoming disorder-related challenges.

Contribution

It provides a disorder-insensitive analysis of magneto-roton energies, bridging the gap between theory and experiment in fractional quantum Hall systems.

Findings

Calculated roton energies match experimental data at 1/3, 2/5, 3/7 fillings

Study circumvents disorder effects by focusing on neutral excitations

Supports the validity of theoretical models for fractional quantum Hall excitations

Abstract

A major obstacle toward a {\em quantitative} verification, by comparison to experiment, of the theory of the excitations of the fractional quantum Hall effect has been the lack of a proper understanding of disorder. We circumvent this problem by studying the {\em neutral} magneto-roton excitations, whose energy is expected to be largely insensitive to disorder. The calculated energies of the roton at 1/3, 2/5 and 3/7 fillings of the lowest Landau level are in good agreement with those measured experimentally.