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Finite-Temperature Phase Diagram of the Hubbard Model

G. Migliorini·A. N. Berker
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Abstract

The finite-temperature phase diagram of the Hubbard model in $d=3$ is obtained from renormalization-group analysis. It exhibits, around half filling, an antiferromagnetic phase and, between 30%--40% electron or hole doping from half filling, a new $τ$ phase in which the electron hopping strength $t$ asymptotically becomes infinite under repeated rescalings. Next to the $τ$ phase, a first-order phase boundary with very narrow phase separation (less than 2% jump in electron density) occurs. At temperatures above the $τ$ phase, an incommensurate spin modulation phase is indicated. In $d=2$, we find that the Hubbard model has no phase transition at finite temperature.

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G. Migliorini, A. N. Berker. 1998-11-17. Finite-Temperature Phase Diagram of the Hubbard Model. https://arxiv.org/abs/cond-mat/9811233

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