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Competition between d-wave superconductivity and antiferromagnetism in the 2D Hubbard model

M. Capone·G. Kotliar
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Abstract

We study the competition of antiferromagnetism and d-wave superconductivity at zero-temperature in the two-dimensional Hubbard model using Cellular Dynamical Mean Field Theory. The interplay between the two phases depends strongly on the strength of the correlation. At strong coupling ($ U \ge 8t$) the two phases do not mix, and a first-order transition takes place as a function of doping between two pure phases. At weak-coupling ($U \le 8t$) the two order parameters coexist within the same solution in a range of doping and the system smoothly evolves from the antiferromagnet to the superconductor. When the transition between the superconducting and the antiferromagetic phases is of the first-order, it is accompanied by a phase separation.

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M. Capone, G. Kotliar. 2006-03-09. Competition between d-wave superconductivity and antiferromagnetism in the 2D Hubbard model. https://doi.org/10.1103/physrevb.74.054513

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