Interaction-Driven Distinctive Electronic States of Artificial Atoms at the ZnO Interface

TL;DR

This study explores the electronic states of ZnO quantum dots with strong electron-electron interactions, revealing unique ground states and magnetization behaviors distinct from traditional semiconductor quantum dots.

Contribution

It demonstrates the impact of enhanced Coulomb interactions in ZnO quantum dots, showing novel ground state properties and magnetization effects not observed in other materials.

Findings

Unique ground state with different properties in ZnO quantum dots

Stronger temperature dependence of magnetization

Paramagnetic-like behavior at high temperatures in quantum-dot helium

Abstract

We have investigated the electronic states of planar quantum dots at the ZnO interface containing a few interacting electrons in an externally applied magnetic field. In these systems, the electron-electron interaction effects are expected to be much stronger than in traditional semiconductor quantum systems, such as in GaAs or InAs quantum dots. In order to highlight that stronger Coulomb effects in the ZnO quantum dots, we have compared the energy spectra and the magnetization in this system to those of the InAs quantum dots. We have found that in the ZnO quantum dots, the signatures of stronger Coulomb interaction manifests in an unique ground state that has very different properties than the corresponding ones in the InAs dot. Our results for the magnetization also exhibits behaviors never before observed in a quantum dot: We have found a stronger temperature dependence and other unexpected features, such as paramagnetic-like behavior at high temperatures for a quantum-dot helium.