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arXiv · 2506.19514

Rare-earth atoms on Nb(110) as a platform to engineer topological superconductivity

David Antognini Silva·Yu Wang·Nicolae Atodiresei·Felix Friedrich·Stefan Blügel·Matthias Bode·Philipp Rüßmann·Artem Odobesko
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Abstract

Helical spin textures in one-dimensional magnetic chains on superconductors can enable topological superconductivity and host Majorana zero modes, independent of the presence of intrinsic spin-orbit coupling. Here, we show that gadolinium (Gd) adatoms, possessing large 4f magnetic moments when placed on a Nb(110) surface, establish indirect exchange interactions mediated by valence electrons, manifesting as Yu-Shiba-Rusinov states. By combining scanning tunneling microscopy and spectroscopy with density functional theory, we analyze the emergence of the Yu-Shiba-Rusinov states in single Gd atoms and Gd dimers and uncover the underlying magnetic interaction mechanisms, on the basis of which we predict by means of spin-dynamics simulations the formation of stable chiral Néel-type spin-spiral configurations in Gd chains. These findings highlight rare-earth magnets as a promising platform for precisely tuning spin-spiral ground states, an essential prerequisite for the realization of topological superconductivity.

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David Antognini Silva, Yu Wang, Nicolae Atodiresei, Felix Friedrich, Stefan Blügel, Matthias Bode, Philipp Rüßmann, Artem Odobesko. 2025-06-24. Rare-earth atoms on Nb(110) as a platform to engineer topological superconductivity. https://arxiv.org/abs/2506.19514

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