Pressure-induced superconductivity in monoclinic RhBi$_2$

KeYuan Ma; Subhajit Roychowdhury; Jonathan Noky; Horst Borrmann; Walter Schnelle; Chandra Shekhar; Sergey A. Medvedev; Claudia Felser

arXiv · 2409.06358

Pressure-induced superconductivity in monoclinic RhBi$_2$

KeYuan Ma·Subhajit Roychowdhury·Jonathan Noky·Horst Borrmann·Walter Schnelle·Chandra Shekhar·Sergey A. Medvedev·Claudia Felser

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Abstract

RhBi$_2$ is a polymorphic system that exhibits two distinct phases. RhBi$_2$ in the triclinic phase has been identified as a weak topological insulator with a van Hove singularity point close to the Fermi energy. Thus, triclinic RhBi$_2$ is expected to exhibit exotic quantum properties under strain or pressure. In this study, we report on the emergence of superconductivity in the monoclinic RhBi$_2$ under external pressures. The electrical resistivity behavior of the monoclinic RhBi$_2$ single crystal is studied at a wide range of applied external pressures up to 40 GPa. We observe a pressure-induced superconductivity with a dome-shaped dependence of the critical temperature on pressure at pressures above 10 GPa. A maximum critical temperature ($T_\mathrm{c}$) value of $T_\mathrm{c}$ = 5.1 K is reached at the pressure of 16.1 GPa. Furthermore, we performed detailed ab initio calculations to understand the electronic band structures of monoclinic RhBi$_2$ under varying pressures. The combination of topology and pressure-induced superconductivity in the RhBi$_2$ polymorphic system may provide us with a new promising material platform to investigate topological superconductivity.

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KeYuan Ma, Subhajit Roychowdhury, Jonathan Noky, Horst Borrmann, Walter Schnelle, Chandra Shekhar, Sergey A. Medvedev, Claudia Felser. 2024-09-10. Pressure-induced superconductivity in monoclinic RhBi$_2$. https://arxiv.org/abs/2409.06358

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