Abstract
The pairing symmetry of interacting Dirac fermions on the -flux lattice is studied with the determinant quantum Monte Carlo and numerical linked-cluster expansion methods. The - (i.e., extended -) and -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 unconventional -wave phase consisting of alternating stripes of - and -wave phases. A complementary mean-field analysis shows that while the - and -wave symmetries individually have nodes in the energy spectrum, the channel is fully gapped. The results represent a new realization of pairing in Dirac systems, connected to the problem of chiral -wave pairing on the honeycomb lattice, which might be more readily accessed by cold-atom experiments.
4 More- Received 24 August 2017
DOI:https://doi.org/10.1103/PhysRevB.97.155146
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