SmFeAsO1-xFxで43Kでの超伝導性が示されている
1Hefei National Laboratory for Physical Sciences at Microscale and Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China. chenxh@ustc.edu.cn
Nature
|May 27, 2008
まとめ
研究者らは,新しい鉄基超伝導体SmFeAsO{1-x) F{-x) を発見し,43Kで超伝導性を示した.この発見は,以前の非銅酸化物の記録を上回り,高温超伝導性研究のための新しい道を開く.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
背景:
- 高過渡温度 (high-T(c)) 超伝導性は,主に酸化銅で観察されています.
- 理論上の最大T ((c) は約40Kで,MgB ((2) は39Kで非銅酸化物の記録を保持しています.
- 層状の稀土金属オキシプニクチド (LnOFeAs) は,超伝導体の新しいクラスとして浮上しています.
研究 の 目的:
- 銅酸化物を超える高T (c) 超伝導性のための新しい材料を探求する.
- SmFeAsO(1-x) F(x) のZrCuSiAs型構造における超伝導性を調査する.
- 高温超伝導性のメカニズムを理解するための新しい材料プラットフォームを確立する.
主な方法:
- ZrCuSiAs型構造を持つSmFeAsO(1-x) F(x) の合成と特徴付けについて.
- 超伝導的移行温度 (T ((c)) を決定するための電気抵抗性測定.
- 大量の超伝導性を確認するための磁気感受性測定.
主要な成果:
- SmFeAsO ((1-x) F ((x)) での大量超伝導性を発見した.
- 超伝導的移行温度 (T ((c)) を 43 K. に達した.
- このT (c) は,銅酸化物以外の超伝導体のこれまでの記録を上回っている.
結論:
- SmFeAsO{1-x) F{x) は,銅酸化物以外の超伝導性の重要な進歩を表しています.
- この新しい材料は,高T (c) 超伝導性の起源に関する基礎研究のための貴重なシステムを提供します.
- この発見は,超伝導現象の調査のために利用可能な材料の範囲を拡大します.
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