Hole-flux Composite Fermion Commensurability Oscillations

TL;DR

This paper reports the observation of strong commensurability oscillations of hole-flux composite fermions near filling factor 1/2 in a high-mobility GaAs quantum well, indicating ballistic transport and allowing mean-free-path estimation.

Contribution

First observation of strong commensurability oscillations of hole-flux composite fermions in a high-mobility system, demonstrating ballistic transport and detailed characterization.

Findings

Oscillations consistent with ballistic, fully spin-polarized composite fermions.

Oscillations exhibit up to third-order minima.

Estimated mean-free-path of about 0.2 μm for composite fermions.

Abstract

We report the observation of commensurability oscillations of hole-flux composite fermions near filling factor $\nu=1/2$ in a high-mobility two-dimensional hole system confined to a GaAs quantum well, and subjected to a weak, strain-induced, unidirectional periodic potential modulation. The oscillations, which are consistent with ballistic transport of fully spin-polarized composite fermions in a weak periodic effective magnetic field, are surprisingly strong and exhibit up to third-order minima. We extract a ballistic mean-free-path of about 0.2 $\mu$m for the hole-flux composite fermions.