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Enhancement of Long Range Antiferromagnetic Order by Nonmagnetic Impurities in the Hubbard Model

M. Ulmke·P. Denteneer·R. Scalettar·G. Zimanyi
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Abstract

The two-dimensional Hubbard model with a bimodal distribution of on-site interactions, P(U_i) = (1-f)δ(U_i-U) + fδ(U_i), is studied using a finite temperature quantum Monte Carlo technique and dynamical mean-field theory. We find long range antiferromagnetic order off half-filling is stabilized by the disorder, due to localization of the dopants on the U=0 sites. Whereas in the clean model there is a single gap at n=1, for nonzero f we find the compressibility and density of states exhibit gaps at two separate fillings.

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M. Ulmke, P. Denteneer, R. Scalettar, G. Zimanyi. 1998-07-01. Enhancement of Long Range Antiferromagnetic Order by Nonmagnetic Impurities in the Hubbard Model. https://doi.org/10.1209/epl%2Fi1998-00301-2

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