マグネティック・カーボン・カーボン
T L Makarova1, B Sundqvist, R Höhne
1Ioffe Physico-Technical Institute, 194021 St Petersburg, Russia. tatiana.makarova@physics.umu.se
Nature
|October 19, 2001
まとめ
研究者らは,分子炭素の形態であるロンボエドールC60に強い磁気信号を発見した. この偶然の発見は,室温でフェロマグネティズムを持つ磁気的に秩序付けられた状態を明らかにしています.
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
- 化学 化学は化学です.
背景:
- グラファイトやC60を含むナノ構造の炭素材料は,多様な性質を示しています.
- 超伝導性は,電子ドーピングされたグラファイトとC60で達成されており,過渡温度は最大52Kに達しています.
- 理論的な研究は,電子の不安定性のために純粋なグラファイトで室温の超伝導性と鉄磁性の可能性を示唆しています.
研究 の 目的:
- ポリメリ化C60.0における超伝導性を調査する.
- ロンボエドールC60.0の磁気特性を探求する.
主な方法:
- 高圧,高温ポリメリゼーションプロセスは,C60.60に適用されます.
- 飽和磁化,ヒステレシス,および温度依存を含む磁性特性の特徴付け.
主要な成果:
- 磁気的に秩序付けられた状態は,ロンボエドールC60.0で意外と観察されました.
- この材料は,室温での飽和磁化やヒステレシスなどの,フェロマグネットの特徴を示しています.
- 温度依存磁化測定により,500K近くのキュリー温度が示されました.
結論:
- C60の高圧,高温ポリメリゼーションは,磁気的に秩序付けられた状態につながる可能性があります.
- ロンボエドールC60は,室温で強力な鉄磁気特性を示しています.
- この発見は,炭素基の材料における磁気現象の研究に新たな道を開く.
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