Spin transitions in an incompressible liquid Coulomb coupled to a quantum dot

TL;DR

This study explores how a quantum dot influences the spin polarization and charge distribution of a nearby quantum Hall liquid at filling factor 2/5, revealing local spin changes and quasihole formation.

Contribution

It demonstrates the local impact of a quantum dot on the spin and charge properties of a quantum Hall liquid, highlighting the role of dot-plane separation.

Findings

Local spin polarization is altered by the quantum dot.

Quasiholes are created and localized near the quantum dot.

Effects depend on the separation distance between dot and electron plane.

Abstract

We report on our investigation of the low-lying energy spectra and charge density of a two-dimensional quantum Hall liquid at $\nu=\frac25$ that is Coulomb coupled to a quantum dot. The dot contains a hole and two/three electrons. We found that any external perturbation (caused by the close proximity of the quantum dot) locally changes the spin polarization of the incompressible liquid. The effect depends crucially on the separation distance of the quantum dot from the electron plane. Electron density distribution in the quantum Hall layer indicates creation of a quasihole that is localized by the close proximity of the quantum dot. Manifestation of this effect in the photoluminescence spectroscopy is also discussed.