La(2) CuO(4+y) の酸素インタースティシャルのスケールフリー構造的組織
Michela Fratini1, Nicola Poccia, Alessandro Ricci
1Department of Physics, Sapienza University of Rome, Piazzale Aldo Moro 2, 00185 Roma, Italy.
Nature
|August 13, 2010
まとめ
La(2) CuO(4+y) 超伝導体における酸素の順序は,フラクタル分布を示している. フラクタルドーパントを含むこの複雑なマイクロ構造は,これらの材料の高温超伝導性を強化しているようです.
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:
- 移行金属酸化物の微細構造,特に高過渡温度 (高T) 銅酸化物の超伝導体は複雑である.
- 酸素のインタースティシャルまたは空白は,これらの材料の散発特性に大きな影響を与えます.
- スパイサー層の酸素インタースティシャルのオーダー現象は,穴の濃度を変えることなく,移行温度に影響することが知られている.
研究 の 目的:
- La(2) CuO(4+y) 高T(c) 超伝導体における酸素間接体の構造的組織を調査する.
- 複雑なシステムの特徴であるスケール不変構造組織が,高T (c) 材料に存在するかどうかを判断する.
- 酸素のインタースティシャルオーダリングと超伝導性の強化の関係を探求する.
主な方法:
- 高T超伝導体La(2)CuO(4+y) の微細構造の分析.
- La(2) O(2+y) 間隔層内の酸素間隔順序の特徴.
- ドーパント組織におけるフラクタル分布パターンの調査.
主要な成果:
- La(2) CuO(4+y) 超伝導体の酸素間位体の順序は,フラクタル分布を示している.
- このフラクタル分布は,最大400マイクロメートルまで広がっている.
- ドーパントのフラクタル分布は,高温超伝導性を強化することが観察されました.
結論:
- La(2) CuO(4+y) の酸素の間位順序は,以前未発見のフラクタル組織を示している.
- このフラクタル微細構造は,高温超伝導性の強化と関連しています.
- この発見は,高T (c) 材料における複雑なシステムの新しい側面を明らかにしています.
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