Evidence of topological Shiba bands in artificial spin chains on superconductors

Lucas Schneider; Philip Beck; Thore Posske; Daniel Crawford; Eric Mascot; Stephan Rachel; Roland Wiesendanger; Jens Wiebe

doi:10.1038/s41567-021-01234-y

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arXiv · 2104.11497

Evidence of topological Shiba bands in artificial spin chains on superconductors

Lucas Schneider·Philip Beck·Thore Posske·Daniel Crawford·Eric Mascot·Stephan Rachel·Roland Wiesendanger·Jens Wiebe

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Abstract

A major challenge in developing topological superconductors for implementing topological quantum computing is their characterization and control. It has been proposed that a p-wave gapped topological superconductor can be fabricated with single-atom precision by assembling chains of magnetic atoms on s-wave superconductors with spin-orbit coupling. Here, we analyze the Bogoliubov quasiparticle interference in atom-by-atom constructed Mn chains on Nb(110) and for the first time reveal the formation of multi-orbital Shiba bands using momentum resolved measurements. We find evidence that one band features a topologically non-trivial p-wave gap as inferred from its shape and particle-hole asymmetric intensity. Our work is an important step towards a distinct experimental determination of topological phases in multi-orbital systems by bulk electron band structure properties only.

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Lucas Schneider, Philip Beck, Thore Posske, Daniel Crawford, Eric Mascot, Stephan Rachel, Roland Wiesendanger, Jens Wiebe. 2021-04-23. Evidence of topological Shiba bands in artificial spin chains on superconductors. https://doi.org/10.1038/s41567-021-01234-y

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