Electron spin polarization by isospin ordering in correlated two-layer quantum Hall systems

TL;DR

This paper reports that in a correlated two-layer quantum Hall system, electron spin polarization is maximized through isospin ferromagnetic order driven by inter-layer Coulomb interactions, surpassing single-layer states.

Contribution

It demonstrates that inter-layer Coulomb correlations induce spontaneous isospin ferromagnetic order, leading to enhanced electron spin polarization in two-layer quantum Hall systems.

Findings

Electron spin polarization is maximized with isospin ferromagnetic order.

Inter-layer Coulomb correlations dominate over single-layer states.

Resistively detected nuclear magnetic resonance confirms the polarization.

Abstract

Enhancement of the electron spin polarization in a correlated two-layer two-dimensional electron system at a total Landau level filling factor of one is reported. Using resistively detected nuclear magnetic resonance, we demonstrate that the electron spin polarization of two closely-spaced two-dimensional electron systems becomes maximized when inter-layer Coulomb correlations establish spontaneous isospin ferromagnetic order. This correlation-driven polarization dominates over the spin polarizations of competing single-layer fractional Quantum Hall states under electron density imbalances.