電子スピン輸送とスピンプレセシンは,室温で単一のグラフェン層で,電子スピン輸送とスピンプレセシンは,室温で単一のグラフェン層で,電子スピン輸送とスピンプレセシンは,室温で単一のグラフェン層で,電子スピントランスポートとスピンプレセシン
Nikolaos Tombros1, Csaba Jozsa, Mihaita Popinciuc
1Physics of Nanodevices, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Nature
|July 17, 2007
まとめ
研究者らは,単一のグラフェン層でマイクロメートルの距離におけるスピン輸送とラモアスピンプレセシオンを観察した. これはグラフェンを示す.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- 材料科学 材料科学とは
- 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.
背景:
- グラフェンのユニークな電子バンド構造は,新しい輸送現象を可能にします.
- グラフェンの低スピン軌道と高精度相互作用は,スピントロニクスにとって有望である.
- 以前の研究では,グラフェンにおける様々な電子輸送現象が観察されました.
研究 の 目的:
- シングルグラフェン層におけるスピン輸送とラモアスピンプレセシオンを調査する.
- スピントロニックアプリケーションにおけるグラフェンの可能性を評価する.
- グラフェンにおけるスピンコヒーレンス長さとコンタクトスピン偏振を決定する.
主な方法:
- 4つの端末のコンタクトを持つ非ローカルなスピンバルブ幾何学を使用しました.
- 薄い酸化物層を介して単一のグラフェン層と接触する鉄磁性コバルト電極を使用しました.
- 様々な温度 (4.2 K,77 K,および室温) で測定されたスピン信号.
主要な成果:
- 電子磁化を反映した明確な双極スピン信号が観測され,延長されたスピンコヒーレンスを示しています.
- マイクロメートルの距離におけるスピントランスポートとラモアスピンプレセシオンが実証された.
- 室温で,最小の温度依存度で,スピンリラクゼーション長さ1.52μmを抽出しました.
- 計算された鉄磁気コンタクトスピン偏振は,約10%である.
結論:
- 単一のグラフェン層は,マイクロメートルの距離を越えてスピン輸送をサポートします.
- グラフェンは,長いスピンコヒーレンス長さがあるため,スピントロニックデバイスに適した材料です.
- 観測された現象は,さまざまな温度範囲で強固である.
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