トポロジカルフッ素吸収によるボロンニトリドナノチューブにおける調節可能な鉄磁性スピンオーダーリング
1Institute of Nano Science, Nanjing University of Aeronautics and Astronautics, No. 29 of Yudao Street, Nanjing 210016, People's Republic of China.
Journal of the American Chemical Society
|May 1, 2009
まとめ
ボロンニトリドナノチューブ上のフッ素原子は,長距離の鉄磁気スピン配列を作り出します. この効果はチューブ半径によって調節可能であり,スピントロニックデバイスでの潜在的なアプリケーションを可能にします.
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
- ナノテクノロジー ナノテクノロジー
背景:
- 酸化ボロンナノチューブ (BNNTs) は,電子アプリケーションのための有望な材料です.
- ナノマテリアルの磁気特性を制御することは,スピントロニクスにとって極めて重要です.
研究 の 目的:
- フッ素を吸収したボルンニトリドナノチューブの磁気特性を調査するために.
- ナノチューブ半径がスピンオーダーリングに及ぼす影響を調査する.
- F-BNNTsで調節可能なピエゾ磁性特性を開発する.
主な方法:
- 第一原理の計算を用いて,BNNTのフッ素吸収をモデル化しました.
- ナノチューブ半径と磁気特性との関係を分析した.
- フェロ磁気順序を制御するために,曲率調節が使用されました.
主要な成果:
- フッ素原子のトポロジカル吸附は,BNNTsで長距離の鉄磁気スピン順序を誘導する.
- スピンの極化と磁気モメントは,ナノチューブ半径の減少とともに増加します.
- 半金属性は,平板板とは異なり,直径3.3 Åで達成されます.
- 半径に依存する行動は,鉄磁気秩序の強化または消し方を可能にします.
結論:
- フッ素で吸収されたBNNTは,チューブ半径に依存する調節可能な鉄磁性特性を示す.
- この半径に依存する振る舞いは,ピエゾ磁性ナノチューブの開発を可能にします.
- 発見は,調節可能なスピントロニックデバイスの設計のための新しい経路を提供します.
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