磁場壁のダイナミクスは,自体の慣性による
Luc Thomas1, Rai Moriya, Charles Rettner
1IBM Almaden Research Center, 650 Harry Road, San Jose, CA, USA. lucthom@us.ibm.com
Science (New York, N.Y.)
|January 6, 2011
まとめ
磁気領域の壁は,電流パルスが停止した後,慣性により長距離を移動します. 正確なポジショニングは,電流パルスのタイミングによって達成され,磁気メモリデバイスの正確な制御を可能にします.
科学分野:
- スピントロニクス (Spintronics) は,スピントロニクス (Spintronics) を開発したものです.
- 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:
- 磁場壁は,スピントロニックデバイスにとって極めて重要です.
- ドメイン壁の動きを正確に制御することは,磁気メモリと論理アプリケーションにとって不可欠です.
- 電流誘発ドメイン壁の動きは,研究の重要な分野です.
研究 の 目的:
- 電流が停止した後の磁場壁の運動ダイナミクスを調査する.
- ドメイン壁の移動と位置づけに影響を与える要因を決定する.
- 磁性ナノワイヤのドメイン壁の正確な位置づけのための方法を確立する.
主な方法:
- ドメイン壁の動きを誘導するために,スピン極化電流パルスを利用します.
- ドメイン壁の動きとリラックスダイナミクスを観察する.
- 現在のパルス持続時間とドメイン壁の位移の間の関係を分析する.
主要な成果:
- ドメインの壁は慣性運動を示し,電流が除去された後にマイクロメートル移動します.
- ドメイン壁のリラクゼーションは,数十ナノ秒間にわたって発生します.
- 領域壁の位移は,初期加速の遅延により,現在のパルス長さに正比例する.
結論:
- ドメイン壁の動きは,慣性と加速のダイナミクスの影響を受けます.
- ドメイン壁の正確な位置付けは,現在のパルスタイミングを制御することによって達成できます.
- この発見は,高度な磁気メモリと論理デバイスの開発に重大な意味を持っています.
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