量子ガスの渦巻カスケードの出現
Nir Navon1, Alexander L Gaunt1, Robert P Smith1
1Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, UK.
Nature
|November 4, 2016
まとめ
量子流体であるボース・ガスの 渦巻状のカスケードが観測されました 量子力学から古典力学まで 渦巻を研究するための新しいシステムです
科学分野:
- 量子物理学
- 流体力学
- 統計的メカニズム
背景:
- 渦巻は長さのスケールにわたるエネルギーカスケードによって特徴付けられ,コルモゴロフとオブホフによって導入された概念です.
- 多重スケールの相互作用により,乱流の観測とシミュレーションは困難です.
- 乱流の観測は プラズマや海洋や金融市場など 様々なシステムに及ぶ
研究 の 目的:
- 制御された量子流体の中で 乱流の出現を実験的に観察する.
- 外部の推進力に対するボースガスの非線形反応を調査する.
- 渦巻を研究するためのモデルシステムとしてボースガスを確立する.
主な方法:
- ボーゼ-アインシュタイン凝縮液を光学箱で準備する.
- 長いスケールで周期的な力を使って システムを均衡から外す
- システムの非線形反応とモメンタム空間分布の観測
- グロス・ピタエフスキー方程式を用いた数値モデリング.
主要な成果:
- ボーゼガスの渦巻カスケードの観測.
- 運動空間における同位体力法則によるカスケードの特徴化.
- 実験的な測定と数値シミュレーションの間の優れた一致性
結論:
- 均一なボースガスは 渦巻の研究の新鮮で有望なプラットフォームとして機能します
- このシステムは量子乱流とその関係と古典乱流の調査を可能にする.
- 乱暴な現象における 量子対古典的な効果の研究を容易にする
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