English

Indications of Unconventional Superconductivity in Doped and Undoped Triangular Antiferromagnets

Superconductivity 2009-10-31 v2 Strongly Correlated Electrons

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\kappa-(BEDT-TTF)2_2X are discussed.

Keywords

Cite

@article{arxiv.cond-mat/9807168,
  title  = {Indications of Unconventional Superconductivity in Doped and Undoped Triangular Antiferromagnets},
  author = {Matthias Vojta and Elbio Dagotto},
  journal= {arXiv preprint arXiv:cond-mat/9807168},
  year   = {2009}
}

Comments

4 pages, 6 figs, results for half-filled systems added, to be published in PRB January 99