ヘリウムにおけるアット秒イオン化とトンネリングの遅延時間測定
P Eckle1, A N Pfeiffer, C Cirelli
1Physics Department, Eidgenössische Technische Hochschule (ETH) Zürich, CH-8093 Zürich, Switzerland.
Science (New York, N.Y.)
|December 6, 2008
まとめ
強い電磁場イオン化中の電子トンネリングのタイミングを測定しました. アト秒角線を用いると,ヘリウム原子のトンネリングの遅延時間は34アト秒未満であることがわかりました.
科学分野:
- 量子力学は,量子力学という
- 原子物理学 原子物理学とは
- 強いフィールドの物理学の力
背景:
- 強いレーザーフィールドの下で原子から電子がトンネル化することは,基本的な量子現象です.
- このトンネル掘削プロセスの正確なタイミングは,超高速な性質のため,長い間論争の的でした.
研究 の 目的:
- 強いフィールドイオン化でトンネリングの遅延時間を実験的に決定する.
- 原子系における電子トンネリングのタイミングに関する論争を解決するために.
主な方法:
- 超高速電子ダイナミクスを探査するための高度な技術であるアット秒角線を活用しました.
- ヘリウム原子に強い電場イオン化を誘導するために,異なる強度で5.5フェムト秒の近赤外線レーザーパルスを使用しました.
- レーザーパルスの円極化を用いて,絶対的な時間基準フレームを確立した.
主要な成果:
- ヘリウムにおけるトンネリングの遅延時間の上限である34アト秒を定めた.
- トンネリングの遅延時間に対して,強度平均の上限12アト秒を決定した.
- 効率的なトンネリングの開始時に観測されたトンネリングの遅延時間 (ケルディッシュパラメータ1.17-1.45).
結論:
- 強いフィールドイオン化におけるトンネリングの遅延時間に関する最初の実験的制約を提供した.
- 結果は,電子トンネルダイナミクスの理論モデルを精錬するために重要なデータを提供します.
- アット秒スケールの時間的な出来事を解くためにアット秒スケールの角線の能力を示した.
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