超伝導性は,アルカリ性土で代用されたLa2CuO4-yの超伝導性です
Science (New York, N.Y.)
|April 3, 1987
まとめ
La(2) CuO4-yセラミクスのアルカリ土ドーピングは,超伝導性を高めます. ストロンチウムドーピングは,より高い発生温度と二磁性を示し,電子の変化が鍵であり,イオンサイズだけではないことを示しています.
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
- 超伝導性は超伝導性である.
背景:
- ランタンコプレート (La(2) CuO4-y) は,高温超伝導体の母化合物である.
- Ca2+),Sr2+),Ba2+などのアルカリ土イオンによるドーピングは,超伝導性を誘発することが知られている.
研究 の 目的:
- La(2)CuO4-y.の超伝導特性に対するCa(2+),Sr(2+),およびBa(2+) ドーピングの影響を調査する.
- 電子変化やイオンサイズ効果が,主に超伝導性の原因であるかどうかを判断する.
主な方法:
- 小さな割合のCa(2+),Sr(2+),およびBa(2+) を添加したLa(2)CuO4-yセラミックの調製.
- 超伝導性の発生と二磁気性を特定するために,電気抵抗性と磁気感受性の測定.
主要な成果:
- ドーピングされたLa(2) CuO4-yのサンプルはすべて,超伝導性の発症を示した.
- Sr(2+) とドーピングされたLa(2)CuO4-yは,Ba(2+) とCa(2+) とのドーピングと比較して,より高い発症温度とより大きな超伝導性誘導ダイアマグネティズムを示しました.
- Sr (((2+) のイオン半径は,La (((3+) のものと類似しており,Laの部位での置換を示唆しています.
結論:
- アルカリ土ドーピングによって誘発される電子変化は,La(2) CuO4-y.における超伝導性の主要な原動力である.
- ストロンチウムドーピングは,特に,有利な電子相互作用と置換パターンによる可能性が高い超伝導性特性を高めるのに効果的です.
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