Transition from an electron solid to the sequence of fractional quantum Hall states at very low Landau level filling factor

TL;DR

This paper reports the observation of a transition from an electron solid to a sequence of fractional quantum Hall states at very low Landau level filling factors, revealing temperature-dependent FQHE states linked to composite fermion series.

Contribution

It provides experimental evidence of a melting transition from an electron crystal to FQHE liquids at low filling factors, following specific composite fermion sequences.

Findings

Observation of local minima in Rxx at specific fractional fillings.

FQHE states appear only above certain temperature thresholds.

Sequence of FQHE states follows composite fermion series from nu=1/6 and 1/8.

Abstract

At low Landau level filling of a two-dimensional electron system, typically associated with the formation of an electron crystal, we observe local minima in Rxx at filling factors nu=2/11, 3/17, 3/19, 2/13, 1/7, 2/15, 2/17, and 1/9. Each of these developing fractional quantum Hall (FQHE) states appears only above a filling factor-specific temperature. This can be interpreted as the melting of an electron crystal and subsequent FQHE liquid formation. The observed sequence of FQHE states follow the series of composite fermion states emanating from nu=1/6 and nu=1/8.