RETRACTED: 分子ワイヤーの室温での超高磁気抵抗
R N Mahato1, H Lülf, M H Siekman
1NanoElectronics Group, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede, Netherlands.
Science (New York, N.Y.)
|July 6, 2013
まとめ
研究者らは,非磁性分子線で超高磁力抵抗 (MR) 効果を発見した. スピンブロックによって引き起こされるこの室温現象は,磁気センサーとデータストレージのアプリケーションに重要な可能性を秘めています.
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:
- 大量の磁気抵抗 (MR) は,磁場感知とデータ保存に不可欠です.
- 通常,大規模なMR効果は,材料の磁気特性に依存しています.
- 室温,小さなフィールドのMRは,実用的なアプリケーションのために非常に望ましいです.
研究 の 目的:
- 非磁気系における大規模なMR効果の可能性を調査する.
- 超高磁気抵抗を達成するための新しいメカニズムを探求する.
- MRアプリケーションのゼオライトに分子ワイヤーを使用する可能性を評価する.
主な方法:
- ゼオライト宿主結晶に埋め込まれた分子ワイヤを使用して1次元のシステムの製造.
- 室温および小さな磁場 (ミリテスラ範囲) で磁気抵抗の実験的な測定.
- 観測されたMR効果の背後にある物理的メカニズムを明らかにするための理論的分析.
主要な成果:
- 室温および小さな磁場では,例外的に大きな磁気抵抗効果 (>2000%) が観察されました.
- 観測されたMR効果は,非磁性,一次元分子ワイヤシステムに存在します.
- この現象は,一次元電子輸送で発生するスピンブロックに起因する.
結論:
- 非磁気系における超高磁気抵抗を達成するための新しいメカニズムが特定されました.
- 低次元のシステムにおけるスピンブロックの一般的性質は,MRアプリケーションのための新しい道を開きます.
- これらの発見は,高度な磁気センサーとデータストレージデバイスの開発に重要な機会をもたらします.
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