電子がトンネルバリアを脱出する時間を解く.
Dror Shafir1, Hadas Soifer, Barry D Bruner
1Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel.
Nature
|May 19, 2012
まとめ
研究者は,探査レーザーを使用して,電子トンネリングの出口時間を測定しました. このブレークスルーは,超高速科学とアット秒実験に不可欠なトンネル掘削後の電子動態を正確に追跡します.
科学分野:
- 量子力学は,量子力学という
- 超高速科学とは
- 原子・分子物理学 原子・分子物理学
背景:
- 電子トンネリングは,強烈なレーザーフィールドによって開始される基本的な量子プロセスです.
- アット秒科学は,アット秒 (10^-18s) の時間スケールで電子のダイナミクスを調査します.
- トンネリングをバリアの外の電子ダイナミクスと結びつけることは,量子力学の重要な課題です.
研究 の 目的:
- 電子がトンネルバリアから出る正確な時間を測定する方法を開発する.
- レーザー誘発トンネル掘削の直後に電子ダイナミクスを調査するために.
- 超高速マルチ電子再配列を解決するためのツールを提供すること.
主な方法:
- 弱い探査場を利用してトンネル化された電子を横方向に誘導する.
- 電子とイオンの再遭遇時に放出される1秒間の光の爆発をモニタリングする.
- 特定の分子軌道からイオン化時間の微妙な遅延を測定する.
主要な成果:
- トンネルバリアからの電子の脱出時間を測定しました.
- 二酸化炭素分子のイオン化遅延を検出することで高い感度を示した.
- トンネル掘削後の電子ダイナミクスの探査のための新しいアプローチを検証しました.
結論:
- 開発された方法は,電子トンネリングの出口時間を正確に決定します.
- このテクニックは,アット秒実験を進め,超高速ダイナミクスを理解するために不可欠です.
- 原子や分子における複雑な電子的再配置を時間的に解明するための一般的なツールを提供します.
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