Moire-Enabled Topological Superconductivity

ORAL · Invited

Abstract



Van der Waals materials provide a versatile platform for realizing a variety of emergent quantum states, including magnetic, correlated, and superconducting states, among others. Interestingly, the tunability of these materials provides an outstanding playground to engineer elusive states of matter typical of complex correlated quantum materials. Here we show that twisted van der Waals heterostructures provide a natural materials platform for realizing topological moire superconductors [1,2], and establish a strategy to probe its hidden properties by leveraging the interplay between moire length scales and local impurities [3]. First, we experimentally demonstrate the emergence of a moire Yu-Shiba-Rusinov electronic structure stemming from the twist between the two van der Waals materials [1]. The moire pattern allows to realize topological states in regions of the phase space that would otherwise be topologically trivial, leading to a topological superconducting state whose topological edge states inherit the moire length. We will furthermore establish [2] a strategy to engineer highly tunable topological superconductivity in twisted graphene bilayers by exploiting a combination of moire patterns and proximity effects to 2D materials. Finally, we show that the interplay between atomic and moire length scales in moire topological superconductors allows to extract the microscopic Hamiltonian using machine learning impurity tomography [3]. Our results show moire physics provides a powerful strategy to engineer ultra-clean artificial topological superconductors using van der Waals materials.

* This work was supported by the Research Council of Finland and the Jane and Aatos Erkko Foundation.

Publication: [1] Shawulienu Kezilebieke, Viliam Vaňo, Md N. Huda, Markus Aapro, Somesh C. Ganguli, Peter Liljeroth, and Jose L. Lado, Nano Lett. 2022, 22, 1, 328–333 (2022)
[2] Maryam Khosravian, Elena Bascones and Jose L. Lado, arXiv:2307.04605 (2023)
[3] Maryam Khosravian, Rouven Koch and Jose L. Lado, arXiv:2308.11400 (2023)

Presenters

  • Jose Lado

    Aalto University

Authors

  • Jose Lado

    Aalto University