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Antiferromagnetism in the 2D Hubbard model: phase transition and local quantities

Roland Muenzner·Adolfo Avella·Ferdinando Mancini
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Abstract

We present a first study of the antiferromagnetic state in the 2D t-t'-U model at finite temperatures by the composite operator method, providing simultaneously a fully self-consistent treatment of the paramagnetic and the AF phase. Near half-filling the critical value of the Coulomb repulsion as a function of t' and the temperature dependence of the magnetization and of the internal energy per site have been studied.

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Roland Muenzner, Adolfo Avella, Ferdinando Mancini. 2002-10-01. Antiferromagnetism in the 2D Hubbard model: phase transition and local quantities. https://doi.org/10.1016/s0921-4526(99)02831-8

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