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arXiv · 1511.04673

Exotic Superconducting Properties in Topological Nodal Semimetal PbTaSe$_2$

Cheng-Long Zhang·Zhujun Yuan·Guang Bian·Su-Yang Xu·Xiao Zhang·M. Zahid Hasan·Shuang Jia
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Abstract

We report the electronic properties of superconductivity in the topological nodal-line semimetal PbTaSe$_2$. Angle-resolved photoemission measurements accompanied by band calculations confirmed the nodal-line band structure in the normal state of single crystalline PbTaSe$_2$. Resistivity, magnetic-susceptibility and specific heat measurements have also been performed on high-quality single crystals. We observed upward features and large anisotropy in upper critical field ($H_{c2}$) measured in-plane (H//\textbf{ab}) and out-plane (H//\textbf{c}), respectively. Especially, $H_{c2}$ measured in H//\textbf{ab} shows sudden upward features rather than a signal of saturation in ultralow temperatures. The specific heat measurements under magnetic field reveal a full superconducting gap with no gapless nodes. These behaviors in this clean noncentrosymmetric superconductor is possibly related to the underlying exotic physics, providing important clue for realization of topological superconductivity.

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Cheng-Long Zhang, Zhujun Yuan, Guang Bian, Su-Yang Xu, Xiao Zhang, M. Zahid Hasan, Shuang Jia. 2015-11-15. Exotic Superconducting Properties in Topological Nodal Semimetal PbTaSe$_2$. https://doi.org/10.1103/physrevb.93.054520

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