高Tc超伝導体の層設計: (Cu,Mo) Sr2 ((Ce,Y) 4Cu2O13+デルタ CuO2平面の間の四重フッ化物層ブロックを持つCuO2
Inga Grigoraviciute1, Hisao Yamauchi, Maarit Karppinen
1Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama 226-8503, Japan.
Journal of the American Chemical Society
|February 8, 2007
まとめ
研究者は,Tc55Kの新しい高Tc超伝導体を合成しました. この発見は,CuO2平面の間に追加のフッ素酸塩層を挿入しても,ドーピングが一定である場合,超伝導性は影響しません.
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
- 化学 化学は化学です.
背景:
- 銅酸化物における高温超伝導性は,しばしばフローライト構造の層を含む.
- これらの層は,隣接するCuO2平面間のブロックブロックとして機能します.
研究 の 目的:
- 新しい高Tc超伝導体相を合成し,特徴づけること.
- 超伝導性に対するフッ素岩層の厚さの影響を調査するために.
主な方法:
- (Cu,Mo) Sr2 (((Ce,Y)) sCu2O (((5+2s+delta)) ホモログ系における新しい相の合成.
- 合成された材料の特性,酸素化とTc測定を含む.
主要な成果:
- 厚さ12μmの4重フッ化物層ブロックを備えた新しいフェーズが成功裏に合成されました.
- この材料は55Kの臨界温度 (Tc) で超伝導性を示した.
- Tcは,穴ドーピングレベルが一定である限り,異なるフッ素岩層の厚さを持つ同類のシリーズの異なるメンバー間で一定でした.
結論:
- (Cu,Mo) -1242相は, (Cu,Mo) Sr2 (((Ce,Y) sCu2O ((5+2s+デルタ)) シリーズの新しいメンバーを表しています.
- 超伝導特性,特にTcは,このシリーズのフローライト層の厚さの変動に対して著しく安定しています.
- 穴ドーピングレベルは,ブロック層の数ではなく,これらの材料のTcを決定する重要な要因です.
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