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Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
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磁気領域の壁の調節可能な量子トンネリング
J Brooke1, T F Rosenbaum, G Aeppli
1The James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637, USA.
Nature
|October 12, 2001
まとめ
研究者らは,磁場による領域壁質量の調整によって,フェロマグネットにおける調節可能な量子トンネリングを実証した. この画期的な発見により,熱力学と量子磁力学ダイナミクスの統一モデリングが可能になった.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- 量子力学は,量子力学という
- マテリアルサイエンス 材料科学
背景:
- フェロマグネットにおけるスピントンネリングのようなマクロの量子現象は,実験的に捉え難いままである.
- 以前の研究は,メソスコピックシステムや乱れたフェロマグネットに焦点を当てていたが,量子プロセスは調節できていなかった.
- 量子プロセスのチューニングの難しさは,実験結果の決定的な解釈を妨げました.
研究 の 目的:
- 量子トンネルの確率の調整を可能にする乱れた磁気システムを記述する.
- 古典的な熱反応と量子トンネリング行動のモデリングを統一する.
- 外部磁場によるドメイン壁のトンネル掘削のチューナビリティを調査する.
主な方法:
- 調節可能な量子トンネリングの確率を持つ無秩序な磁気システムを利用した.
- 高温で熱的に活性化された反応をモデル化した古典的反応.
- 統一されたフレームワーク内で低温での非熱的,トンネルの振る舞いをモデル化しました.
- 領域壁を,外界の磁場によって調整可能な固定質量を持つ粒子として記述した.
主要な成果:
- 量子トンネリングの確率を調整できる乱れた磁気系を示した.
- 単一のフレームワーク内で,古典的な熱と量子トンネルのダイナミクスを両方モデル化することに成功しました.
- 外部磁場がドメイン壁の有効な"質量"を変えることで量子トンネルを調節できることを示した.
結論:
- 乱れた磁気系の中で調節可能な量子トンネリングを達成した.
- クラシックと量子磁力学ダイナミクスの統一モデルを確立した.
- 外部磁場は,フェロマグネットにおける量子トンネリング現象を制御するための方法を提供します.
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