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Unconventional Superconducting Symmetry in a Checkerboard Antiferromagnet

Huai-Xiang Huang·You-Quan Li·Jing-Yu Gan·Yan Chen·Fu-Chun Zhang
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Abstract

We use a renormalized mean field theory to study the Gutzwiller projected BCS states of the extended Hubbard model in the large $U$ limit, or the $t$-$t'$-$J$-$J'$ model on a two-dimensional checkerboard lattice. At small $t'/t$, the frustration due to the diagonal terms of $t'$ and $J'$ does not alter the $d_{x^2-y^2}$-wave pairing symmetry, and the negative (positive) $t'/t$ enhances (suppresses) the pairing order parameter. At large $t'/t$, the ground state has an extended s-wave symmetry. At the intermediate $t'/t$, the ground state is $d+id$ or $d+is$-wave with time reversal symmetry broken.

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Huai-Xiang Huang, You-Quan Li, Jing-Yu Gan, Yan Chen, Fu-Chun Zhang. 2007-03-09. Unconventional Superconducting Symmetry in a Checkerboard Antiferromagnet. https://doi.org/10.1103/physrevb.75.184523

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