Fractionally charged skyrmions in fractional quantum Hall effect

TL;DR

This paper demonstrates the existence of fragile fractional skyrmions near 1/3 filling in the fractional quantum Hall effect, detectable via resonant inelastic light scattering, revealing insights into composite fermion interactions.

Contribution

It provides experimental evidence of fractional skyrmions slightly away from 1/3 filling, highlighting their spectral signatures and role in understanding residual interactions.

Findings

Fractional skyrmions exist near 1/3 filling in the fractional quantum Hall regime.

Resonant inelastic light scattering detects these skyrmions as resonances below the spin wave mode.

The results shed light on the residual interactions between composite fermions.

Abstract

The fractional quantum Hall effect has inspired searches for exotic emergent topological particles, such as fractionally charged excitations, composite fermions, abelian and nonabelian anyons and Majorana fermions. Fractionally charged skyrmions, which support both topological charge and topological vortex-like spin structure, have also been predicted to occur in the vicinity of 1/3 filling of the lowest Landau level. The fractional skyrmions, however, are anticipated to be exceedingly fragile, suppressed by very small Zeeman energies. Here we show that, slightly away from 1/3 filling, the smallest manifestations of the fractional skyrmion exist in the excitation spectrum for a broad range of Zeeman energies, and appear in resonant inelastic light scattering experiments as well-defined resonances slightly below the long wavelength spin wave mode. The spectroscopy of these exotic bound states serves as a sensitive tool for investigating the residual interaction between composite fermions, responsible for delicate new fractional quantum Hall states in this filling factor region.