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arXiv · 2011.05470

Spin-polarized Yu-Shiba-Rusinov states in an iron based superconductor

Dongfei Wang·Jens Wiebe·Ruidan Zhong·Genda Gu·Roland Wiesendanger
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Abstract

Yu-Shiba-Rusinov (YSR) bound states appear when a magnetic atom interacts with a superconductor. Here, we report on spin-resolved spectroscopic studies of YSR states related with Fe atoms deposited on the surface of the topological superconductor FeTe0.55Se0.45 using a spin-polarized scanning tunneling microscope. We clearly identify the spin signature of pairs of YSR bound states at finite energies within the superconducting gap having opposite spin polarization as theoretically predicted. In addition, we also observe zero-energy bound states for some of the adsorbed Fe atoms. In this case, a spin signature is found to be absent indicating the absence of Majorana bound states associated with Fe adatoms on FeTe0.55Se0.45.

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Dongfei Wang, Jens Wiebe, Ruidan Zhong, Genda Gu, Roland Wiesendanger. 2020-11-11. Spin-polarized Yu-Shiba-Rusinov states in an iron based superconductor. https://doi.org/10.1103/physrevlett.126.076802

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