Temperature dependence of surface superconductivity in t-PtBi$_2$

Julia Besproswanny; Sebastian Schimmel; Yanina Fasano; Grigory Shipunov; Saicharan Aswartham; Danny Baumann; Bernd Büchner; Christian Hess

arXiv · 2507.10187

Temperature dependence of surface superconductivity in t-PtBi$_2$

Julia Besproswanny·Sebastian Schimmel·Yanina Fasano·Grigory Shipunov·Saicharan Aswartham·Danny Baumann·Bernd Büchner·Christian Hess

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Abstract

The Weyl semimetal trigonal PtBi$_2$ has recently been identified as a promising candidate material for intrinsic topological surface superconductivity emerging from the Fermi arc states of the material with a sizeable superconducting gap. We report the temperature evolution of the superconducting excitation spectrum using scanning tunneling spectroscopy in the range of $8-45\,$K. A large low-temperature gap in the order of $\Delta \approx 9\,$meV and a closing of the gap around $T_c \approx 45\,$K is observed. Thus, our results confirm the previously indicated high $T_c$-like superconductivity in t-PtBi$_2$.

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Julia Besproswanny, Sebastian Schimmel, Yanina Fasano, Grigory Shipunov, Saicharan Aswartham, Danny Baumann, Bernd Büchner, Christian Hess. 2025-07-14. Temperature dependence of surface superconductivity in t-PtBi$_2$. https://arxiv.org/abs/2507.10187

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