Coexistence of superconductivity and antiferromagnetism in self-doped bilayer t-t'-J model

J. Y. Gan; M. Mori; T. K. Lee; S. Maekawa

doi:10.1103/physrevb.78.094504

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arXiv · 0807.2688

Coexistence of superconductivity and antiferromagnetism in self-doped bilayer t-t'-J model

J. Y. Gan·M. Mori·T. K. Lee·S. Maekawa

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Abstract

A self-doped bilayer t-t'-J model of an electron- and a hole-doped planes is studied by the slave-boson mean-field theory. A hopping integral between the differently doped planes, which are generated by a site potential, are renormalized by the electron-electron correlation. We find coexistent phases of antiferromagnetic (AFM) and superconducting orders, although the magnitudes of order parameters become more dissimilar in the bilayer away from half-filling. Fermi surfaces (FS's) with the AFM order show two pockets around the nodal and the anti-nodal regions. These results look like a composite of electron- and hole-doped FS's. In the nodal direction, the FS splitting is absent even in the bilayer system, since one band is flat due to the AFM order.

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J. Y. Gan, M. Mori, T. K. Lee, S. Maekawa. 2008-07-17. Coexistence of superconductivity and antiferromagnetism in self-doped bilayer t-t'-J model. https://doi.org/10.1103/physrevb.78.094504

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