超流体ヘリウムにおける反陽子ヘリウムの高解像度レーザー共振

Anna Sótér^1,2, Hossein Aghai-Khozani^1,3, Dániel Barna^4,5

¹Max-Planck-Institut für Quantenoptik, Garching, Germany.

Nature

|March 17, 2022

まとめ

超流体ヘリウムの反陽子ヘリウム原子は,高解像度レーザースペクトロスコーピーを可能にする鋭いスペクトルラインを示します. この突破は異質な原子の詳細な研究と宇宙の反物質の検出を可能にします

科学分野:

原子と分子物理学
反物質物理学
低温物理学

背景:

液体中の原子の光学スペクトル線が大きく広がり,高解像度のスペクトル検査を阻害する.
超流動的ヘリウムは透明で冷たい,惰性的な環境を提供しますが,埋め込まれた原子のスペクトル拡大は持続します.

研究の目的:

超流体ヘリウムに埋め込まれた反陽子ヘリウムのスペクトル線幅を調査する.
超流体ヘリウムにおける異質な原子の高解像度レーザースペクトロスコピーの可能性を探求する.

主な方法:

超流体ヘリウムに反陽子ヘリウム原子を埋め込む
レーザー共鳴を観察し,スペクトル線の幅を測定する.
電子対反陽子のスピン・スピン相互作用による超微細構造の分析

主要な成果:

超流体ヘリウム中の反陽子ヘリウムは,その可視スペクトルラインでサブギガヘルツの線幅を示しています.
超流体相への移行時に線幅の急激な減少が観察されました.
10^6分の2の相対的なスペクトル解像度を持つ超精細な構造を分解した.

結論:

超流動ヘリウムにより,高解像度レーザースペクトロスコーピーは可能になる.
このテクニックは,他の反核原子,メゾン,およびハイパーオンを研究するために適用できます.
鋭いスペクトル線は,宇宙線反陽子と反デュートロン検出を容易にする.

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