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arXiv · 1110.6613

Correlation-driven chiral superconductivity and chiral spin order in doped kagome lattice

Shun-Li Yu·Jian-Xin Li
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Abstract

We study the electronic instabilities of the Hubbard model in the 1/6 hole-doped Kagome lattice using the variational cluster approach. The 1/6 hole doping is unique in the sense that the Fermi level is at the von Hove singularity and the Fermi surface has a perfect nesting. In this case, a density wave is usually realized. However, we demonstrate here that the chiral $d_{x^{2}-y^{2}}+id_{xy}$ superconducting state is most favorable when a small Hubbard interaction U(U<3.0t) is introduced, and a scalar chiral spin order is realized at large U(U>5.0t). Between them, a spin-disordered insulating state is proposed.

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Shun-Li Yu, Jian-Xin Li. 2011-10-30. Correlation-driven chiral superconductivity and chiral spin order in doped kagome lattice. https://doi.org/10.1103/physrevb.85.144402

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