フェロ磁性CoPt3ナノワイヤ:fccからL1(2) へと構造的進化
Hao Ming Chen1, Chia Fen Hsin, Po Yuan Chen
1Department of Chemistry, National Taiwan University, Taipei 106, Taiwan.
Journal of the American Chemical Society
|October 8, 2009
まとめ
コバルト・プラチナ (CoPt3) ナノワイヤの磁性特性は,熱的に誘発された相変化によって強化されます. ランダムな合金からオーダーされたL1(2) 構造へのこの移行は,強制性と正方形性を改善します.
科学分野:
- 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
- マグネチズム (磁気) とは
背景:
- コバルト・プラチナ (CoPt3) 合金は磁気特性で知られている.
- ナノ構造の材料は,ユニークな物理的特性を提供します.
- 段階変換の制御は,材料の特性を調節するために非常に重要です.
研究 の 目的:
- CoPt3ワイヤー配列の磁気特性とナノ構造を調査する.
- CoPt3ナノワイヤで発生する相変化を理解するために.
- 原子分布を磁気行動と相関させるため.
主な方法:
- CoPt3ワイヤー配列の製造には,電解と多孔性アルミニウムテンプレートを使用します.
- 段階移行を研究するためのX線吸収分析.
- 磁気特性の測定 (強制力,正方形).
主要な成果:
- X線吸収により,CoPt3ナノワイヤの相変化が確認されました.
- 移行は,ランダムな合金からアニソトロピー的にオーダーされたCoPt3 (L1(2)) 構造にありました.
- この相変化により,強引性や正方形性を含む磁気特性が大幅に強化されました.
結論:
- CoPt3ナノワイヤの熱的に誘発された相移行機構が明らかにされ",クラスター内のクラスター"の中間状態と相互拡散が含まれています.
- CoPt3ナノワイヤの原子分布と磁気特性との間に強い相関関係がある.
- 発見は,ナノワイヤの構造的順序を介して磁気特性を制御するための洞察を提供します.
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