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Quantum Hall Ferrimagnetism in lateral quantum dot molecules

Ramin M. Abolfath·Pawel Hawrylak
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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 $ν=2$ and $ν=1$.

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Ramin M. Abolfath, Pawel Hawrylak. 2006-07-25. Quantum Hall Ferrimagnetism in lateral quantum dot molecules. https://doi.org/10.1103/physrevlett.97.186802

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