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arXiv · 1409.7859

Superconductivity and structural distortion in BaPt$_2$As$_2$

W. B. Jiang·C. Y. Guo·Z. F. Weng·Y. F. Wang·Y. H. Chen·Y. Chen·G. M. Pang·T. Shang·X. Lu·H. Q. Yuan
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Abstract

We successfully synthesized the BaPt$_2$As$_2$ single crystals and studied their structural and physical properties at low temperatures. BaPt$_2$As$_2$ crystallizes in the CaBe$_2$Ge$_2$-type tetragonal structure (P4/nmm) at room temperature and undergoes a first-order structural transition at $T_S\simeq 275$ K, which is likely associated with a charge-density-wave (CDW) instability. BCS-type superconductivity with two subsequent transitions at $T_{c1}=1.67$K and $T_{c2}$=1.33K are observed in this compound. Thus, BaPt$_2$As$_2$ may serve as a new system for studying the interplay of superconductivity and the CDW order.

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W. B. Jiang, C. Y. Guo, Z. F. Weng, Y. F. Wang, Y. H. Chen, Y. Chen, G. M. Pang, T. Shang, X. Lu, H. Q. Yuan. 2014-09-28. Superconductivity and structural distortion in BaPt$_2$As$_2$. https://doi.org/10.1088/0953-8984/27/2/022202

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