Hubbard-Thomas-Fermi Theory of Transition Metal Oxide Heterostructures

Wei-Cheng Lee; A. H. MacDonald

doi:10.1016/j.physb.2007.10.191

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arXiv · 0708.0554

Hubbard-Thomas-Fermi Theory of Transition Metal Oxide Heterostructures

Wei-Cheng Lee·A. H. MacDonald

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Abstract

We demonstrate that the charge distributions in Hubbard-model representations of transition metal oxide heterojucntions can be described by a Thomas-Fermi theory in which the energy is approximated as the sum of the electrostatic energy and the uniform three-dimensional Hubbard model energy per site at the local density equals to a constant. When charged atomic layers in the oxides are approximated as two-dimensional sheets with uniform charge density, the electrostatic energy is simply evaluated. We find that this Thomas-Fermi theory can reproduce results obtained from full Hartree-Fock theory for various different heterostructures. We also show explicitly how Thomas-Fermi theory can be used to estimate some key properties qualitatively.

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Wei-Cheng Lee, A. H. MacDonald. 2007-08-03. Hubbard-Thomas-Fermi Theory of Transition Metal Oxide Heterostructures. https://doi.org/10.1016/j.physb.2007.10.191

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