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Indications of Unconventional Superconductivity in Doped and Undoped Triangular Antiferromagnets

Matthias Vojta·Elbio Dagotto
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Abstract

The possibility of superconductivity in doped and undoped triangular antiferromagnets is discussed. Using the Bethe-Salpeter (B-S) equation, it is shown that the exchange of RPA paramagnons on a triangular lattice Hubbard model leads to strong pairing correlations at and near half-filling. The dominant states for this system correspond to d-wave singlet (even-frequency) and s-wave triplet (odd-frequency) pairing. Analytical techniques applied to the hole-doped t-J model yield similar results. A t_1-t_2 Hubbard model interpolating between square (t_1=0) and triangular (t_1=t_2) lattices has a tendency to only d-wave singlet pairing for t_1/t_2 <= 0.8. Experimental consequences for organic compounds $κ$-(BEDT-TTF)$_2$X are discussed.

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Matthias Vojta, Elbio Dagotto. 1998-10-30. Indications of Unconventional Superconductivity in Doped and Undoped Triangular Antiferromagnets. https://doi.org/10.1103/physrevb.59.r713

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