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Does long-range antiferromagnetism help or inhibit superconductivity?

Liliana Arrachea·A. A. Aligia
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Abstract

We analyze the possible existence of a superconducting state in a background with long-range antiferromagnetism. We consider a generalized Hubbard model with nearest-neighbor correlated hopping in a square lattice. Near half filling, the model exhibits a d-wave-Bardeen-Cooper-Schrieffer (BCS) solution in the paramagnetic state. The superconducting solution would be enhanced by the antiferromagnetic background if the contribution of triplet pairs with d-wave symmetry and total momentum (pi, pi) could be neglected. However, we find that due to their contribution, the coexistence of superconductivity and long-range antiferromagnetism is ruled out for large values of the Coulomb repulsion U. Spin-density wave fluctuations (SDWF) do not change this result.

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Liliana Arrachea, A. A. Aligia. 1998-05-19. Does long-range antiferromagnetism help or inhibit superconductivity?. https://arxiv.org/abs/cond-mat/9805198

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