Spin-orbit coupling effect on quantum Hall ferromagnets with vanishing Zeeman energy

TL;DR

This paper explores how spin-orbit coupling influences the phase diagram of quantum Hall ferromagnets in narrow wells with negligible Zeeman energy, revealing transitions from easy-axis to helical states affecting transport and topological defects.

Contribution

It provides the first detailed phase diagram of quantum Hall ferromagnets considering strong spin-orbit coupling and vanishing Zeeman energy.

Findings

Transition from easy-axis to helical spin states as Zeeman energy decreases

Spin-orbit coupling modifies transport and NMR properties

Topological defect structures are affected by the spin configuration

Abstract

We present the phase diagram of a ferromagnetic quantum Hall effect liquid in a narrow quantum well with vanishing single-particle Zeeman splitting, $\epsilon_{{\rm Z}}$ and pronounced spin-orbit coupling. Upon decreasing $\epsilon_{{\rm Z}}$, the spin-polarization field of a liquid takes, first, the easy-axis configuration, followed by the formation of a helical state, which affects the transport and NMR properties of a liquid and the form of topological defects in it. The analysis is extended over high odd integer filling factors.