Exotic pairing state in quasicrystalline superconductors under magnetic field

Shiro Sakai; Ryotaro Arita

doi:10.1103/physrevresearch.1.022002

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arXiv · 1905.01487

Exotic pairing state in quasicrystalline superconductors under magnetic field

Shiro Sakai·Ryotaro Arita

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Abstract

We theoretically study the effect of a magnetic field on quasicrystalline superconductors, by modelling them as the attractive Hubbard model on the Penrose-tiling structure. We find that at low temperatures and under a high magnetic field there appears an exotic superconducting state with the order parameter changing its sign in real space. We discuss the state in comparison with the Fulde-Ferrell-Larkin-Ovchinnikov state proposed many years ago for periodic systems, clarifying commonalities and differences. It is remarkable that, even in the absence of periodicity, the electronic system finds a way to keep a coherent superconducting state with a spatially sign-changing order parameter compatible with the underlying quasiperiodic structure.

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Shiro Sakai, Ryotaro Arita. 2019-05-04. Exotic pairing state in quasicrystalline superconductors under magnetic field. https://doi.org/10.1103/physrevresearch.1.022002

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