関連する実験動画
Updated: Jul 12, 2026

10:09
Fast Imaging Technique to Study Drop Impact Dynamics of Non-Newtonian Fluids
Published on: March 5, 2014
超流動性の証拠は,0.15ケルビンでヘリウム-4滴の内部にあるパラ-水素クラスターにある
1Max-Planck-Institut für Strömungsforschung, Bunsenstrabetae 10, 37073 Göttingen, Germany. General Physics Institute, Russian Academy of Sciences, 117942 Moscow, Russia.
まとめ
この研究では,赤外線光譜を用いて,ヘリウム滴の分子を調べました. 結果は,ヘリウム以外の液体における超流動性の最初の証拠を示唆しています.
科学分野:
- 量子流体と固体について
- スペクトロスコーピーは,スペクトロスコーピーを用います.
- 低温物理 低温物理
背景:
- 超流動性は,液体ヘリウムで観測される量子力学的現象です.
- 他のシステムにおける超流動性の理解は,基本的な物理を明らかにすることができます.
- ヘリウム滴は,量子現象を研究するためのユニークな環境を提供します.
研究 の 目的:
- ヘリウム-4 ((4) He) と混合 (4) He/(3) He滴におけるカルボニル硫化物 (OCS) 分子の振る舞いを調査する.
- 異なるヘリウム環境におけるOCS軸の周りの角運動量の興奮を調査する.
- ヘリウム以外の液体における超流動性の証拠を提供する.
主な方法:
- 赤外線スペクトロスコピーは,パラ水素 (pH(2) またはオルトデュテリウム (oD(2) でドーピングされたOCS分子を分析するために使用されました.
- 実験は,0.38 Kの純粋な (4) He ドロップと0.15 Kの混合 (4) He/(3) He ドロップで行われました.
- 角運動量刺激に関連するスペクトル特性が監視された.
主要な成果:
- 純粋な (4) ヘリウム滴のスペクトル特徴は,pH (pH) と OD (OD) の両方に刺激された角運動量を示した.
- より冷たい混合 (4) He/(3) He滴では,これらの特徴はoD ((2)) にわたって持続したが,pH ((2) において消滅した.
- pH(2) のスペクトル特徴の消失は,角運動量刺激の停止を示唆している.
結論:
- 観測されたスペクトル特性の変化は,混合滴の超流動性の発生と一致しています.
- この研究は,ヘリウム以外の液体系における超流動性に関する最初のスペクトル学的証拠を提示しています.
- この発見は,新しい超流動的な環境における量子現象の探索のための新しい道を開く.
関連する概念動画
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