Spin-texture and magneto-roton excitations at nu=1/3

TL;DR

This study reports the first direct observation of neutral spin texture excitations at filling factor 1/3, revealing their behavior under varying magnetic fields and temperature, and exploring their role in quantum Hall transport.

Contribution

First direct detection of neutral spin texture excitations at nu=1/3 using resonant inelastic light scattering, showing their energy crossing with magneto-roton modes and temperature-dependent intensity.

Findings

Spin texture excitations involve two spin flips.

Their energy crosses magneto-roton modes at a critical field ratio.

The mode intensity increases with temperature, indicating phase competition.

Abstract

Neutral spin texture ST excitations at nu=1/3 are directly observed for the first time by resonant inelastic light scattering. They are determined to involve two simultaneous spin- flips. At low magnetic fields, the ST energy is below that of the magneto-roton minimum. With increasing in-plane magnetic field these modes energies cross at a critical ratio of the Zeeman and Coulomb energies of eta_c=0.020 +- 0.001. Surprisingly, the intensity of the ST mode grows with temperature in the range in which the magneto-roton modes collapse. The temperature dependence is interpreted in terms of a competition between coexisting phases supporting different excitations. We consider the role of the ST excitations in activated transport at nu=1/3.