Signature of odd-frequency equal-spin triplet pairing in the Josephson current on the surface of Weyl nodal loop semimetals

Paramita Dutta; Annica M. Black-Schaffer

doi:10.1103/physrevb.100.104511

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arXiv · 1902.10014

Signature of odd-frequency equal-spin triplet pairing in the Josephson current on the surface of Weyl nodal loop semimetals

Paramita Dutta·Annica M. Black-Schaffer

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Abstract

We theoretically predict proximity-induced odd-frequency (odd-$ω$) pairing on the surface of a Weyl nodal loop semimetal, characterized by a nodal loop Fermi surface and drumhead-like surface states (DSSs), attached to conventional spin-singlet $s$-wave superconducting leads. Due to the complete spin polarization of the DSS, odd-$ω$ equal-spin triplet pairing is present, and we show that it gives rise to a finite Josephson current. Placing an additional ferromagnet in the junction can also generate odd-$ω$ mixed-spin triplet pairing, but the pairing and current is not affected if the magnetization is orthogonal to the DSS spin-polarization, which further confirms the equal-spin structure of the pairing.

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Paramita Dutta, Annica M. Black-Schaffer. 2019-09-12. Signature of odd-frequency equal-spin triplet pairing in the Josephson current on the surface of Weyl nodal loop semimetals. https://doi.org/10.1103/physrevb.100.104511

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