アルカリ土金属で満たされたスカートルジットの超伝導性 BaxIr4X12 (X = As, P)
Yanpeng Qi1, Hechang Lei1, Jiangang Guo1
1Materials Research Center for Element Strategy, Tokyo Institute of Technology , 4259 Yokohama, Japan.
Journal of the American Chemical Society
|June 6, 2017
まとめ
研究者らは超伝導性イリジウムプニクチド,BaxIr4X12を発見し,バリウムの充填が金属の移行を誘導する. BaxIr4As12は4.8 Kに達し,BaxIr4P12は5.6 Kに達した.
科学分野:
- 固体物理学
- 材料科学
- 超伝導性
背景:
- 充填されたスクーテラダイト構造は ユニークな電子特性を提供します
- イリジウムプニクチドは,超伝導性の可能性のある材料のクラスです.
研究 の 目的:
- イリジウムピニクチド BaxIr4X12 (X = As and P) の電子特性および超伝導性に対するバリウム (Ba) 充填の影響を調査する.
- 超伝導性の移行温度を決定し,これらの材料の超伝導性の種類を分類する.
主な方法:
- BaxIr4As12とBaxIr4P12化合物の合成と特徴づけについて
- 電子特性と超伝導的移行温度をBa含有量の関数として測定する (x).
主要な成果:
- バリウム充填は,BaxIr4X12の電子特性を大幅に変化させます.
- 非金属から金属への電子的移行は,バの含有量増加とともに観察された.
- 最高の超伝導変換温度は,BaxIr4As12で4.8K,BaxIr4P12で5.6Kであった.
結論:
- バリウムで満たされたイリジウムプニクチドは,調節可能な電子特性と超伝導性を示す.
- BaxIr4X12における超伝導性は,中間の結合強さを示すBardeen-Cooper-Schrieffer (BCS) 理論と一致している.
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