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arXiv · 1903.07901

Quantum oscillations in the non-centrosymmetric superconductor and topological nodal-line semimetal PbTaSe$_2$

Xitong Xu·Zhibo Kang·Tay-Rong Chang·Hsin Lin·Guang Bian·Zhujun Yuan·Zhe Qu·Jinglei Zhang·Shuang Jia
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Abstract

We observed quantum oscillations in thermoelectric and magnetic torque signals in non-centrosymmetric superconductor PbTaSe$_2$. One oscillatory frequency stems from the orbits formed by magnetic breakdown, while others are from two-dimensional-like Fermi surfaces near the topological nodal rings. Our comprehensive understanding of the Fermi surface topology of PbTaSe$_2$, including nailing down the Fermi level and detecting the Berry phases near the nodal rings, is crucial for searching plausible topological superconductivity in its bulk and surface states.

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Xitong Xu, Zhibo Kang, Tay-Rong Chang, Hsin Lin, Guang Bian, Zhujun Yuan, Zhe Qu, Jinglei Zhang, Shuang Jia. 2019-03-19. Quantum oscillations in the non-centrosymmetric superconductor and topological nodal-line semimetal PbTaSe$_2$. https://doi.org/10.1103/physrevb.99.104516

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