Two ground-state modifications of quantum-dot beryllium

TL;DR

This paper investigates the electronic properties of a four-electron quantum dot system, revealing different ground state correlation patterns and distinct Wigner molecule formation mechanisms in strong-interaction regimes.

Contribution

It identifies two distinct ground-state modifications with different electron correlation behaviors and Wigner molecule formation pathways in quantum-dot beryllium.

Findings

Degenerate ground states exhibit qualitatively different electron-electron correlations.

Wigner molecule formation occurs via different mechanisms in these ground states.

The study provides insights into strong-interaction regimes in quantum dots.

Abstract

Exact electronic properties of a system of four Coulomb-interacting two-dimensional electrons in a parabolic confinement are reported. We show that degenerate ground states of this system are characterized by qualitatively different internal electron-electron correlations, and that the formation of Wigner molecule in the strong-interaction regime is going on in essentially different ways in these ground states.