Spin excitations in the Fractional Quantum Hall regime at $\nu\lesssim1/3$

TL;DR

This study uses inelastic light scattering to explore spin excitations in the fractional quantum Hall regime near filling factor 1/3, revealing a composite fermion Landau level structure with four attached flux quanta.

Contribution

It provides experimental evidence for spin flip excitations of composite fermions with four flux quanta, elucidating the Landau level structure in this regime.

Findings

Observation of a spin mode below the Zeeman energy.

Filling factor dependence consistent with composite fermion theory.

Identification of a Landau level structure in the $ u oughly1/3$ regime.

Abstract

We report inelastic light scattering experiments in the fractional quantum Hall regime at filling factors $\nu\lesssim1/3$. A spin mode is observed below the Zeeman energy. The filling factor dependence of the mode energy is consistent with its assignment to spin flip excitations of composite fermions with four attached flux quanta ($\phi$=4). Our findings reveal a composite fermion Landau level structure in the $\phi$=4 sequence.