狭間半導体における超伝導性 RbBi11/3Te6
Christos D Malliakas1, Duck Young Chung1, Helmut Claus1
1Materials Science Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.
Journal of the American Chemical Society
|October 18, 2016
まとめ
研究者は,狭い帯域の隙間を持つ新しい層状の材料であるRbBi11 / 3Te6で超伝導性を発見しました. 化学チューニングにより,その臨界温度 (Tc) が10%まで上昇し,新しい超伝導体開発の道が開けました.
科学分野:
- 材料科学
- 凝縮物質物理学
- 固体化学
背景:
- 超伝導性は,物質が臨界温度以下で電気抵抗をゼロにするところの量子力学的現象です.
- 層状の材料は,アニゾトロプ的構造によってユニークな電子特性を提供します.
- 新しい超伝導物質の発見は エネルギー伝達や磁気浮揚などの 技術の発展に不可欠です
研究 の 目的:
- 新しい層状化合物RbBi11 / 3Te6における超伝導性を発見し,特徴づけること.
- この新しい材料システムの超伝導特性に対する化学置換の影響を調査する.
- 同型シリーズを確立し,新しい超伝導体の開発の可能性を探求する.
主な方法:
- RbBi11/3Te6のポリクリスタルインゴットとオリエンテッド単体結晶の合成
- バンドギャップ測定を含む構造と電子特性の特徴.
- RbBi11/3-ySbySexTe6-xを生成するために,SeとSbを体系的に置換する.
- 超伝導体移行温度 (Tc) と超伝導体体積分を測定する.
主要な成果:
- RbBi11 / 3Te6で超伝導性が発見され,約3.2Kで急激に変化した.
- この材料は,単一結晶のほぼ100%の超伝導体積分によって確認された大量超伝導性を表しています.
- 化学的置換 (SeとSb) は,超伝導的移行の調節性を示し,Tcを10%まで増加させた.
- RbBi11 / 3Te6は,無限のBi2Te3のような層を持つ新しい同類系Rb[Bi2n+11 / 3Te3n+6]の最初のメンバーを表しています.
結論:
- RbBi11 / 3Te6は,新しい同類系に属する新しいバルク超伝導体です.
- 電子構造はドーピングと置換で化学的に調整でき 新しい超伝導体ファミリーを提供します
- この発見は 超伝導物質の探査と設計に 新たな基盤を提供しました
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