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Topological doping of repulsive Hubbard models

A. Kesting·C. Timm
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Abstract

The spin configuration induced by single holes and hole pairs doped into stoichiometric, antiferromagnetic cuprates is considered. Unrestricted Hartree-Fock calculations for the three-band Hubbard model are employed to study spin-polaron and vortex-like (meron) solutions. Meron solutions for a single hole are found to be metastable with higher energy than spin polarons. We observe that the meron solution shifts from site-centered to bond-centered as the interaction is increased. Meron-antimeron solutions for hole pairs are found to be unstable. The results are in agreement with earlier findings for the one-band Hubbard model. However, we find that the Hubbard interaction of the one-band model has to be chosen similar to the one of the three-band model to obtain comparable results, not of the order of the charge-transfer gap, as previously expected.

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A. Kesting, C. Timm. 2003-08-12. Topological doping of repulsive Hubbard models. https://doi.org/10.1016/s0921-4526(03)00492-7

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