Wigner solids of domain wall skyrmions

TL;DR

This paper provides experimental evidence that domain wall skyrmions form a Wigner solid phase in quantum Hall ferromagnets, using nonlocal resistance and NMR techniques to characterize their properties and phase transitions.

Contribution

It introduces a novel experimental approach to detect and analyze DW skyrmions and demonstrates their formation as a Wigner solid in quantum Hall systems, highlighting overlooked quantum states.

Findings

DW skyrmions form a Wigner solid ground state

Nonlocal resistance and NMR reveal DW skyrmion properties

Phase transitions depend on temperature, filling factor, and magnetic fields

Abstract

Detection and characterization of a different type of topological excitations, namely the domain wall (DW) skyrmion, has received increasing attention because the DW is ubiquitous from condensed matter to particle physics and cosmology. Here we present experimental evidence for the DW skyrmion as the ground state stabilized by long-range Coulomb interactions in a quantum Hall ferromagnet. We develop an alternative approach using nonlocal resistance measurements together with a local NMR probe to measure the effect of low-current-induced dynamic nuclear polarization and thus to characterize the DW under equilibrium conditions. The dependence of nuclear spin relaxation in the DW on temperature, filling factor, quasiparticle localization, and effective magnetic fields allows us to interpret this ground state and its possible phase transitions in terms of Wigner solids of the DW skyrmion. These results demonstrate the importance of studying the intrinsic properties of quantum states that has been largely overlooked.