自己組み立てコバルトナノ結晶のスーパーグリットでスピン依存のトンネリング
C T Black1, C B Murray, R L Sandstrom
1IBM Research Division, T. J. Watson Research Center, Yorktown Heights, NY 10598, USA. ctblack@us.ibm.com
Science (New York, N.Y.)
|November 10, 2000
まとめ
コバルトナノ結晶配列は,スピン依存の電子輸送を示しています. 彼らの磁気抵抗は低温で10%に達し,より高い温度ではスピンフリップ分散によって制限されます.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- 材料科学は材料科学である.
- ナノテクノロジー ナノテクノロジー
背景:
- 自己組み立てナノ構造は,ユニークな電子特性を提供します.
- コバルトナノ結晶は,スピントロニックアプリケーションに有望である.
研究 の 目的:
- コバルトナノ結晶配列におけるスピン依存電子輸送を調査する.
- これらの装置の磁気抵抗性能を特徴づけるために.
主な方法:
- 10nmコバルトナノ結晶の周期配列の製造.
- 電流-電圧の特性を測定する.
- 低温 (20K以下) で磁気抵抗の分析.
主要な成果:
- 装置は,スピン依存の電子伝送を示す.
- 電流・電圧データは,単電子トンネリングモデルと一致しています.
- 低温では磁気抵抗比が10%に近づく.
- Spin-flip scatteringは,磁気抵抗に影響を与える重要な要因として特定されました.
結論:
- 自己組み立てコバルトナノクリスタル配列は,スピントロニックデバイスに有効です.
- 輸送メカニズムと分散の理解は,パフォーマンスの最適化に不可欠です.
- デバイスの性能は温度とバイアス電圧に依存しています.
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