SmFeAsOシステムにおけるドーピングによる超伝導性
Yong Liang Chen1, Cui Hua Cheng, Ya Jing Cui
1Key Laboratory of Advanced Technology of Materials (Ministry of Education of China), Superconductivity R&D Center (SRDC), Mail Stop 165, Southwest Jiaotong University, Chengdu, Sichuan 610031, China.
Journal of the American Chemical Society
|July 15, 2009
まとめ
SmFeAsOにおけるイリジウム (Ir) ドーピングは16Kで超伝導性を誘導する.この5D移行金属ドーピングは,電荷貯蔵層ドーピングとは異なる方法でAs-Fe-As結合角度を変更する.
科学分野:
- 固体物理 固体物理学
- マテリアルサイエンス 材料科学
- 超伝導性は超伝導性である.
背景:
- サマリウム鉄酸化アルセニド (SmFeAsO) は,鉄基超伝導体ファミリーの親化合物である.
- ドーピング効果を理解することは,超伝導体の特性を調節するために不可欠です.
研究 の 目的:
- SmFeAsOに5d移行金属イリジウム (Ir) のドーピングが及ぼす影響を調査する.
- 超伝導性の誘導とその構造変化との相関を調査する.
主な方法:
- イリジウム (Ir) の化学ドーピングは,SmFeAsO格子に約15%の原子 %で作用する.
- 結合角度の変化,特にAs-Fe-As結合角度 (β) を決定する構造分析.
主要な成果:
- 16Kの臨界温度 (Tc) で超伝導性の誘導に成功した.
- IrドーピングによるAs-Fe-As結合角度 (β) の減少が観察されました.
- ベータに対するIrドーピングの効果が,電荷貯蔵庫層におけるドーピングとは異なることを実証した.
結論:
- イリジウムによる5d移行金属ドーピングは,SmFeAsOに超伝導性を誘導する効果的な戦略です.
- 観測された構造変化 (βの減少) は,誘発超伝導性の重要な要因である.
- ドーピングサイトは,構造的反応と超伝導特性に大きな影響を与えます.
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