122 KのT1 ((Ba,Ca) 2Ca3Cu4O10.5+8) で,連続した4つの銅層による大量超伝導
Science (New York, N.Y.)
|September 2, 1988
まとめ
超伝導的移行温度 (T ((c)) は,新しい4層の酸化物超伝導体における酸化銅層とともに増加します. 普遍的なスケーリング曲線は,関連材料の超伝導性におけるTl (Bi) 層の重要な役割を明らかにしています.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- 固体化学 固体化学
背景:
- 銅酸超伝導体の超伝導移行温度 (T ((c)) は,一般に,酸化銅の平面の数とともに増加します.
- T ((c) を支配する要因を理解することは,新しい超伝導材料の開発に不可欠です.
研究 の 目的:
- 4層の[CuO(2) ](-2層の酸化物超伝導体の超伝導性能を調査する.
- 銅酸化物層の数とT (c) との関係を確立する.
- 超伝導性における特定の層の役割を特定する.
主な方法:
- 高純度 (>80%) の4層の[CuO(2) ](-2層の酸化物超伝導体を作る.
- 結晶学的識別のための磁気配列.
- 超伝導的移行温度 (T) (c) の分析
主要な成果:
- 銅酸化物層で観測されたT (c) の増加は,4層のシステムで継続しています.
- 様々なBiおよびTl酸化物超伝導体のT (c) 値を結びつけるマスタースケーリング曲線が提案されました.
- Tl (Bi) 層は,超伝導性にとって不可欠であると特定されました.
結論:
- 4層の[CuO(2) ](-2層の酸化物超伝導体は,関連材料の動向と一致する強化されたT(c) を表しています.
- 統一されたスケーリング関係は,これらの酸化物における超伝導性に対するTl ((Bi)) 層の重要な貢献を強調しています.
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