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Coexistence of d_{x^2-y^2}-Wave Superconductivity and Antiferromagnetism Induced by a Staggered Field

Yasuhiro Saiga·Masaki Oshikawa
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Abstract

The two-dimensional t-J model in a staggered field is studied by exact diagonalization of small clusters. For the low-hole-density region and a realistic value of J/t, it is found that the presence of a staggered field strengthens the attraction between two holes. With increasing field, the d_{x^2-y^2}-wave superconducting correlations are enhanced while the extended-s-wave ones hardly change. This implies that coexistence of the d_{x^2-y^2}-wave superconducting order and the commensurate antiferromagnetic order occurs in a staggered field.

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Yasuhiro Saiga, Masaki Oshikawa. 2003-10-14. Coexistence of d_{x^2-y^2}-Wave Superconductivity and Antiferromagnetism Induced by a Staggered Field. https://doi.org/10.1103/physrevb.68.094511

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