Comment on "Observation of a Pinning Mode in a Wigner Solid with nu=1/3 Fractional Quantum Hall Excitations"

TL;DR

This paper critiques the interpretation of a pinned mode in a Wigner solid at nu=1/3, proposing that the rotating-Wigner-molecule approach better explains the experimental findings than the interacting composite fermion theory.

Contribution

It introduces the rotating-Wigner-molecule approach as a comprehensive framework for understanding crystalline correlations near nu=1/3 in the FQHE regime.

Findings

Rotating-Wigner-molecule approach explains experimental data.

Crystalline correlations at nu~1/3 are consistent with the rotating-Wigner-molecule model.

The ICF theory lacks reports of crystalline correlations at nu~1/3.

Abstract

A recent letter [H. Zhu et al., Phys. Rev. Lett. 105, 126803 (2010)] reports the first measurements of a pinned mode in a Wigner solid at the (electronic) nu = 1/3 fractional quantum Hall effect (FQHE) filling. The authors suggest that an interpretation of their findings may be found within the interacting composite fermion (ICF) theory. However, to date there is no record reporting crystalline correlations for nu ~ 1/3 obtained from ICF theory, or related theories. We argue that an appropriate interpretation of these findings follows naturally from the rotating-Wigner-molecule approach, which (with inclusion of the rovibrational spectrum of the molecule) encompasses both the crystalline and liquid aspects in the FQHE regime (in particular for nu=1/3, as well as in its neighborhood created by deviations of nu from 1/3, as revealed experimentally).