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arXiv · 1711.09283

Pt-Bi Antibonding Interaction: The Key Factor for Superconductivity in Monoclinic BaPt2Bi2

Xin Gui·Lingyi Xing·Xiaoxiong Wang·Guang Bian·Rongying Jin·Weiwei Xie
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Abstract

In the search for superconductivity in BaAu2Sb2-type monoclinic structure, we have successfully synthesized a new compound BaPt2Bi2, which crystallizes in the space group P21/m (S.G. 11; Pearson symbol mP10) according to a combination of powder and single crystal X-ray diffraction and scanning electron microscopy. Sharp electrical resistivity drop and large diamagnetic magnetization below 2.0 K indicates it owns the superconducting ground state. This makes BaPt2Bi2 the first reported superconductor in mono-clinic BaAu2Sb2-type structure, a previously unappreciated structure for superconductivity. First-principles calculations considering the spin-orbit coupling indicate that Pt-Bi anti-bonding interaction plays a critical role in inducing superconductivity.

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Xin Gui, Lingyi Xing, Xiaoxiong Wang, Guang Bian, Rongying Jin, Weiwei Xie. 2017-11-25. Pt-Bi Antibonding Interaction: The Key Factor for Superconductivity in Monoclinic BaPt2Bi2. https://arxiv.org/abs/1711.09283

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