Excitons of Composite Fermions

TL;DR

This paper investigates the excitations of composite fermions in fractional quantum Hall states, developing new methods to analyze their dispersion relations and confirming the effectiveness of unprojected composite fermion theory.

Contribution

It introduces novel techniques for studying large systems of composite fermion excitons and provides detailed dispersion data supporting unprojected composite fermion theory.

Findings

Interaction energy of excitons matches unprojected composite fermion predictions

Developed methods enable analysis of large system excitations

Detailed dispersion relations of composite fermion excitons obtained

Abstract

The low-energy excitations of filled Landau levels (LL's) of electrons involve promotion of a single electron from the topmost filled LL to the lowest empty LL. These are called excitons or collective modes. The incompressible fractional quantum Hall states are understood as filled LL's of composite fermions, and the low-energy neutral excitations are excitons of composite fermions. New techniques are developed to study large systems, which provide detailed information about the dispersions of the composite fermion excitons. In particular, it is found that the interaction energy of the exciton is well described by the `unprojected' composite fermion theory.