鉄の非磁気状態における超伝導性は,圧力下にある
K Shimizu1, T Kimura, S Furomoto
1Department of Physical Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan. kshimizu@mp.es.osaka-u.ac.jp
Nature
|July 19, 2001
まとめ
鉄は,高圧 (1530 GPa) に晒されると,低温 (2K以下) で超伝導体となる. これは鉄で起こります.
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
背景:
- 鉄磁気と超伝導性は,通常,従来の超伝導体で競合する現象です.
- 金属は,低温で非磁気状態でも超伝導性を示すことができる.
- 鉄は10 GPa以上の圧力で非磁性構造に変形し,この段階では超伝導性が予測されます.
研究 の 目的:
- 高圧下における非磁性鉄の超伝導性の可能性を調査する.
- 鉄の超伝導性特性を高圧で予測することを実験的に確認するために.
主な方法:
- 鉄の高圧合成と特徴化について.
- 電気抵抗を温度と圧力の関数として測定する.
- 超伝導性を確認するためにマイスナー効果の検出.
主要な成果:
- 鉄は2K以下の温度で超伝導性を示す.
- 鉄の超伝導性は,15~30GPaの圧力で観測される.
- 抵抗力の顕著な低下とマイスナー効果は,超伝導的移行を確認する.
結論:
- 高圧誘導による非磁性鉄は,超伝導体になり得る.
- これらの発見は,超伝導性の競合する相に関する従来の理解に挑戦しています.
- 圧迫下での鉄の超伝導的振る舞いは,材料科学の研究のための新しい道を開く.
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