Quantum Hall Ferrimagnetism in lateral quantum dot molecules

TL;DR

This paper investigates the magnetic phases in coupled lateral quantum dot molecules under quantum Hall conditions, revealing ferrimagnetic and ferromagnetic states influenced by electron interactions, magnetic field, and tunneling parameters.

Contribution

It introduces a detailed phase diagram of spin states in quantum dot molecules using Hartree-Fock Configuration Interaction calculations.

Findings

Identification of ferrimagnetic and ferromagnetic phases in quantum Hall regime.

Ferrimagnetic phase arises from spatially imbalanced spin droplets.

Ferromagnetic phases occur at specific filling factors between ν=2 and ν=1.

Abstract

We demonstrate the existance of ferrimagnetic and ferromagnetic phases in a spin phase diagram of coupled lateral quantum dot molecules in the quantum Hall regime. The spin phase diagram is determined from Hartree-Fock Configuration Interaction method as a function of electron numbers N, magnetic field B, Zeeman energy, and tunneling barrier height. The quantum Hall ferrimagnetic phase corresponds to spatially imbalanced spin droplets resulting from strong inter-dot coupling of identical dots. The quantum Hall ferromagnetic phases correspond to ferromagnetic coupling of spin polarization at filling factors between $\nu=2$ and $\nu=1$.