渦巻量子ガスの合成分散とカスケードフロー
Nir Navon1, Christoph Eigen2, Jinyi Zhang2
1Department of Physics, Yale University, New Haven, CT 06520, USA. nir.navon@yale.edu kazuya_fujimoto@rover.nuap.nagoya-u.ac.jp.
Science (New York, N.Y.)
|October 5, 2019
まとめ
研究者は乱流の量子ガスのスケールインヴァリアントフロースを測定し,乱流のゼロの法則を示しました. この研究は直接のエネルギーカスケードで 粒子フルスに直接アクセスし 量子乱流のダイナミクスを洞察します
科学分野:
- 量子物理学
- 流体力学
- 凝縮物質物理学
背景:
- エネルギー伝達に不可欠なスケール不変の流れを示します
- これらの流れを実験で直接測定することは 実験的に困難です
- 量子ガスは 根本的な渦巻現象を研究するための ユニークなプラットフォームを提供します
研究 の 目的:
- 乱流の量子ガスのスケールインヴァリアントフローの直接測定を行う.
- 合成分散スケールを用いて 渦巻のゼロの法則を実験的に証明する.
- 運動空間における直接的なエネルギーカスケードの 安定前状態のダイナミクスを調査する.
主な方法:
- エネルギー注入のための時間周期的な力を使って 3Dボースガスで直接のエネルギーカスケードを生成した.
- 調整可能なトラップの深さを使用して,合成の分散スケールとして高モメンタムカットオフ (k_D) を作成します.
- 粒子の流れとカスケードダイナミクスにアクセスするために時間解像度測定を行った.
主要な成果:
- 合成分散スケール (k_D) でモメンタムシェルを通過する粒子の流れを測定しました.
- k_Dのチューナビリティを通して, 渦巻のゼロの法則を証明した.
- 運動空間におけるカスケードフロントの 独特の前静止状態のダイナミクスを捉えました
結論:
- スケール不変のフローの直接測定は,乱流の量子ガスで達成可能である.
- 実験の設定は,基本的な乱流法則の実証を可能にします.
- 乱流の気流の 暫定的な振る舞いに 前例のない洞察力を 提供しています
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