2016年4月
Fabrication of new superconducting materials, CaxK1-xCy (0 < x < 1)
CARBON
- 巻
- 100
- 号
- 開始ページ
- 641
- 終了ページ
- 646
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1016/j.carbon.2016.01.071
- 出版者・発行元
- PERGAMON-ELSEVIER SCIENCE LTD
Metal intercalation to graphite produces various types of superconductors. The highest superconducting transition temperature T-c (onset temperature, T-c(onset), of 11.5 K) was found in Ca intercalated graphite, denoted CaC6.T-c(onset) increased up to 15.1 K at 7.5 GPa, implying a positive pressure dependence. However, no new metal-intercalated graphite superconductors with T-c(onset) higher than 11.5 K at ambient pressure have so far been reported. To search for new graphite superconductors, we successfully synthesized binary-element-intercalated graphite, CaxK1-xCy. Their structure resembles that of KC8. T-c increased continuously with increasing x. Furthermore, the pressure dependence of T-c in Ca0.6K0.4C8 was investigated over a wide pressure range from 0-43 GPa. T-c (= 9.6 K at 0 GPa) increased to 11.6 K at 3.3 GPa, and decreased to 2.0 K at 41 GPa. This behavior is similar to that of CaC6, albeit with a lower maximum T-c. Xray diffraction patterns were measured under high pressures of 0-24 GPa, and suggest a structural transition at 15 GPa. Evidence is given for superconducting graphite involving binary metal intercalation. (C) 2016 Elsevier Ltd. All rights reserved.
- リンク情報
- ID情報
-
- DOI : 10.1016/j.carbon.2016.01.071
- ISSN : 0008-6223
- eISSN : 1873-3891
- Web of Science ID : WOS:000369961400072