Magnetism of quantum dot clusters: A Hubbard model study
Strongly Correlated Electrons
2009-11-13 v1 Mesoscale and Nanoscale Physics
Abstract
Magnetic properties of two and three-dimensional clusters of quantum dots are studied with exact diagonalization of a generalized Hubbard model. We study the weak coupling limit, where the electrons interact only within a quantum dot and consider cases where the second or third harmonic oscillator shell is partially filled. The results show that in the case of half-filled shell the magnetism is determined by the antiferromagnetic Heisenberg model with spin 1/2, 1 or 3/2, depending on the number of electrons in the open shell. For other fillings the system in most cases favors a large total spin, indicating a ferromagnetic coupling between the dots.
Cite
@article{arxiv.0804.4745,
title = {Magnetism of quantum dot clusters: A Hubbard model study},
author = {J. -P. Nikkarila and M. Koskinen and M. Manninen},
journal= {arXiv preprint arXiv:0804.4745},
year = {2009}
}
Comments
9 pages, 9 figures