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arXiv · 2105.00561

Correlation-induced triplet pairing superconductivity in graphene-based moiré systems

Yang-Zhi Chou·Fengcheng Wu·Jay D. Sau·Sankar Das Sarma
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Abstract

Motivated by the possible non-spin-singlet superconductivity in the magic-angle twisted trilayer graphene experiment, we investigate the triplet-pairing superconductivity arising from a correlation-induced spin-fermion model on a honeycomb lattice. We find that the $f$-wave pairing is favored due to the valley-sublattice structure, and the superconducting state is time-reversal symmetric, fully gapped, and non-topological. With a small in-plane magnetic field, the superconducting state becomes partially polarized, and the transition temperature can be slightly enhanced. Our results apply qualitatively for the triplet-pairing superconductivity in graphene-based moiré systems, which is fundamentally distinct from triplet superconductivity in $^3$He and ferromagnetic superconductors.

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Yang-Zhi Chou, Fengcheng Wu, Jay D. Sau, Sankar Das Sarma. 2021-11-16. Correlation-induced triplet pairing superconductivity in graphene-based moiré systems. https://doi.org/10.1103/physrevlett.127.217001

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