Charge and Spin Reconstruction in Quantum Hall Strips

TL;DR

This paper investigates how electron-electron interactions influence charge and spin arrangements in a Quantum Hall strip, revealing transitions from unpolarized to polarized states and charge reconstructions depending on confinement sharpness and magnetic field.

Contribution

It introduces a detailed analysis of charge and spin transitions in Quantum Hall strips, highlighting the role of confinement and magnetic field in these phenomena, and connects findings to recent tunneling experiments.

Findings

Spin-unpolarized to spin-polarized transition as magnetic field increases.

Charge reconstruction of a single spin species occurs before spin polarization in weak confinements.

Spontaneous spin polarization develops at the softer side of the potential in sharp confinements.

Abstract

We study the effect of electron-electron interactions on the charge and spin structures of a Quantum Hall strip in a triangularly confined potential. We find that the strip undergoes a spin-unpolarized to spin-polarized transition as a function of magnetic field perpendicular to the strip. For sharp confinements the spin-polarization transition is spontaneous and first develops at the softer side of the triangular potential which shows up as an "eye-structure" in the electron dispersion. For sufficiently weak confinements this spin-polarization transition is preceded by a charge reconstruction of a single spin species, which creates a spin-polarized strip of electrons with a width of the order of the magnetic length detached from the rest of the system. Relevance of our findings to the recent momentum resolved tunneling experiments is also discussed.