We demonstrate the formation of robust zero energy modes close to magnetic impurities in the iron-based superconductor FeSe1−xTex. We find that the Zeeman field generated by the impurity favors a spin-triplet inter-orbital pairing as opposed to the spin-singlet intra-orbital pairing prevalent in the bulk. The preferred spin-triplet pairing preserves time-reversal symmetry and is topological, as robust, topologically-protected zero modes emerge at the boundary between regions with different pairing states. Moreover, the zero modes form Kramers doublets that are insensitive to the direction of the spin polarization or to the separation between impurities. We argue that our theoretical results are consistent with recent experimental measurements on FeSe1−xTex.
@article{arxiv.2207.12425,
title = {Anomalous Shiba states in topological iron-based superconductors},
author = {Areg Ghazaryan and Ammar Kirmani and Rafael M. Fernandes and Pouyan Ghaemi},
journal= {arXiv preprint arXiv:2207.12425},
year = {2022}
}