ナノスケールの磁域は,メソスコピック磁石に存在します
1M. Hehn, K. Ounadjela, J.-P. Bucher, Institut de Physique et Chimie des Materiaux de Strasbourg, 23 rue du Loess, 67037 Strasbourg Cedex, France. F. Rousseaux and D. Decanini, L2M/CNRS, 196 Avenue Henri Ravera, 92225 Bagneux, France. B. Bartenlian and C. Chappert, Institut d'Electronique Fondamentale, Universite Paris-Sud, 91405 Orsay Cedex, France.
Science (New York, N.Y.)
|June 21, 1996
まとめ
コバルトナノドットの磁域パターンは,連続フィルムと異なる. ナノドット幾何学は,これらの複雑なパターンを制御し,磁気特性と磁気化の逆転に影響を与えます.
科学分野:
- 材料科学 材料科学とは
- 凝縮物質物理学 凝縮物質物理学
- ナノテクノロジー ナノテクノロジー
背景:
- 三次元ナノ構造材料は,連続フィルムと比較してユニークな磁気特性を発揮します.
- ナノ構造物の磁域の振る舞いを理解することは,高度な磁気装置の開発に不可欠です.
研究 の 目的:
- サブマイクロメートルのコバルトドットにおける磁場パターンに対する幾何学の影響を調査する.
- ナノドット厚さを変化させることで磁域幅の調節性を探求する.
- 磁気化の逆転プロセスにおけるこれらのドメイン構成の役割を分析する.
主な方法:
- 高解像度磁力顕微鏡 (MFM) を用いてコバルトナノドットを研究した.
- 異なる幾何学的な寸法を持つ亜マイクロメートルのサイズのコバルトドットが製造されました.
- 集積平均ヒステレスループを測定し,磁気化の逆転を観察しました.
主要な成果:
- コンセントリックなリングや渦状の渦状のスパイラルを含む複雑な磁域パターンが観察されました.
- 幾何学的に制約された磁気領域の幅は,点の厚さを変更することによって調整可能であることが判明しました.
- これらの特定のドメイン構成は,磁気化の逆転プロセスで有意であることが判明しました.
結論:
- ナノ構造磁気材料の幾何学は,基本的に磁気領域の振る舞いを決定する.
- コバルトナノドットの調節可能な磁域構造は,制御された磁気デバイスのアプリケーションの可能性を秘めています.
- 渦巻ドメイン構成は,これらのナノドットの磁化逆転機構において重要な役割を果たします.
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