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Phase Diagram of the Hubbard Model: Beyond the Dynamical Mean Field

M. Jarrell·Th. Maier·M. H. Hettler·A. N. Tahvildarzadeh
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Abstract

The Dynamical Cluster Approximation (DCA) is used to study non-local corrections to the dynamical mean field phase diagram of the two-dimensional Hubbard model. Regions of antiferromagnetic, d-wave superconducting, pseudo-gapped non-Fermi liquid, and Fermi liquid behaviors are found, in rough agreement with the generic phase diagram of the cuprates. The non-local fluctuations beyond the mean field both suppress the antiferromagnetism and mediate the superconductivity.

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M. Jarrell, Th. Maier, M. H. Hettler, A. N. Tahvildarzadeh. 2000-11-16. Phase Diagram of the Hubbard Model: Beyond the Dynamical Mean Field. https://doi.org/10.1209/epl%2Fi2001-00557-x

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