Tl2Ba2Ca2Cu3O10の結晶構造,125K超伝導体である
Science (New York, N.Y.)
|April 29, 1988
まとめ
(A(III) O) (((2) A(2) ((II) Can-1CunO2+2nとして表される新しい高温超伝導体シリーズは,より多くの銅-酸素シートを持つより高い移行温度を示しています. 化合物Tl ((2) Ba ((2) Ca ((2) Cu ((3) O ((10) は,およそ125 Kで最も高い移行温度を示しています.
科学分野:
- マテリアルサイエンス 材料科学
- 固体物理 固体物理学
- ケミストリー 化学
背景:
- 高温超伝導体は,先進技術にとって極めて重要です.
- 材料構造と超伝導特性との関係は,重要な研究分野である.
- 以前の研究では,層状のカップレートの様々な組成を調べた.
研究 の 目的:
- 新しい高温超伝導体シリーズを調査するためです.
- これらの材料の構造的および超伝導的性質を決定する.
- 銅と酸素のシートの数と移行温度との相関を調査する.
主な方法:
- 超伝導化合物の合成と特徴付け.
- 構造分析のための単結晶X線 difraktion. 構造分析のための単結晶X線 difraktion.
- 電子顕微鏡で,相互成長と構造的変異を特定します.
主要な成果:
- (A(III) O) ((2) A(2) ((II) Can-1CunO2+2nという新しい超伝導体系が特定されました.
- 最も高い移行温度 (約. 125 K) は,Tl(2) Ba(2) Ca(2) Cu(3) O(10) (n=3) で観察されました.
- 電子顕微鏡では,n=5の相互増殖を明らかにし,140 Kの近くでの発症行動に潜在的に責任がある.
結論:
- 銅-酸素シート (n) の数は,この超伝導体シリーズの移行温度に大きな影響を与える.
- Tl ((2) Ba ((2) Ca ((2) Cu ((3) O ((10) は,大量の高温超伝導性の重要な進歩を表しています.
- 相互成長構造のさらなる調査は,さらに高い移行温度につながる可能性があります.
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