Superconducting Pairing Symmetries in Anisotropic Triangular Quantum Antiferromagnets

Abstract

Motivated by the recent discovery of a low temperature spin liquid phase in layered organic compound $\kappa$-(ET)${}_2$Cu${}_2$(CN)${}_3$ which becomes a superconductor under pressure, we examine the phase transition of Mott insulating and superconducting (SC) states in a Hubbard-Heisenberg model on an anisotropic triangular lattice. We use a renormalized mean field theory to study the Gutzwiller projected BCS wavefucntions. The half filled electron system is a Mott insulator at large on-site repulsion $U$, and is a superconductor at a moderate $U$. The symmetry of the SC state depends on the anisotropy, and is gapful with $d_{x^2-y^2}+i{d}_{xy}$ symmetry near the isotropic limit and is gapless with $d_{x^2-y^2}$ symmetry at small anisotropy ratio.

6 pages, 5 figures

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Cited by in corpus (3)

• Absence of superconductivity in the half-filled band Hubbard model on the anisotropic triangular lattice
• Exotic Superconducting Phases of Ultracold Atom Mixtures on Triangular Lattices
• Unconventional Superconducting Symmetry in a Checkerboard Antiferromagnet