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arXiv · 1708.07256

Exotic pairing symmetry of interacting Dirac fermions on a $π$ flux lattice

Huaiming Guo·Ehsan Khatami·Yao Wang·Thomas P. Devereaux·Rajiv R. P. Singh·Richard T. Scalettar
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Abstract

The pairing symmetry of interacting Dirac fermions on the $π$-flux lattice is studied with the determinant quantum Monte Carlo and numerical linked cluster expansion methods. The extended $s^*$- (i.e. extended $s$-) and d-wave pairing symmetries, which are distinct in the conventional square lattice, are degenerate under the Landau gauge. We demonstrate that the dominant pairing channel at strong interactions is an exotic $ds^*$-wave phase consisting of alternating stripes of $s^*$- and d-wave phases. A complementary mean-field analysis shows that while the $s^*$- and d-wave symmetries individually have nodes in the energy spectrum, the $ds^*$ channel is fully gapped. The results represent a new realization of pairing in Dirac systems, connected to the problem of chiral d-wave pairing on the honeycomb lattice, which might be more readily accessed by cold-atom experiments.

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Huaiming Guo, Ehsan Khatami, Yao Wang, Thomas P. Devereaux, Rajiv R. P. Singh, Richard T. Scalettar. 2018-04-11. Exotic pairing symmetry of interacting Dirac fermions on a $π$ flux lattice. https://doi.org/10.1103/physrevb.97.155146

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