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arXiv · 2402.11007

Stability of quasiperiodic superconductors

Nicole Sabina Ticea·Julian May-Mann·Jiewen Xiao·Erez Berg·Trithep Devakul
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Abstract

We study the effects of quasiperiodicity on the stability of conventional and unconventional superconductors. Quasiperiodicity is modelled using the three-dimensional Aubry-Andre model, a system in which electrons are coupled to a translation-symmetry-breaking potential that is incommensurate with the underlying lattice. Upon increasing the strength of the quasiperiodic potential, the single-particle eigenstates undergo a transition from a ballistic to a diffusive character. Here, we study the instability of the model towards superconductivity. We find that in the ballistic regime, the system is unstable towards both $s$-wave and $p$-wave superconductivity. In contrast, only the conventional $s$-wave instability survives in the intermediate diffusive regime. Our results suggest a version of Anderson's theorem for quasiperiodic systems, relating the normal state dynamics to the stability of conventional and unconventional superconductivity. These findings are relevant vis-a-vis recent studies of superconductivity in quasiperiodic moire structures.

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Nicole Sabina Ticea, Julian May-Mann, Jiewen Xiao, Erez Berg, Trithep Devakul. 2024-02-16. Stability of quasiperiodic superconductors. https://arxiv.org/abs/2402.11007

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