単一のフェルミガスにおける普遍的量子粘度

C Cao¹, E Elliott, J Joseph

¹Department of Physics, Duke University, Durham, NC 27708, USA.

Science (New York, N.Y.)

|December 15, 2010

まとめ

研究者は,原子のフェルミ・ガスの中で,普遍的な水力学を探求した. 彼らは低温と高温でシーア粘度を測定し,高温で正確なT ^ 3 / 2のスケーリングを見つけ,それを完璧な流体行動と比較しました.

科学分野:

量子物理学とは,量子物理学のことです.
凝縮物質物理学凝縮物質物理学
原子物理学原子物理学とは

背景:

共振相互作用を持つフェルミガスは,理論的に普遍的な水力学を示すことが予測されています.
輸送係数は,シーア粘度と同様に,密度と温度の一般的な関数であると考えられます.

研究の目的:

低温と高温の両方でフェルミガスの切断粘度を実験的に測定する.
予測された普遍的な水力動力学的行動と粘性の温度スケーリングを検証するために.

主な方法:

低温シーア粘性は,呼吸モードのダッピングを使用して測定されました.
高温切断粘性は,原子雲のアニゾトロプ的膨張を分析することによって決定された.
摩擦と加熱を含む普遍的な水力力学方程式を使用して,粘度値を抽出しました.

主要な成果:

切断粘性は,異なる温度体制で測定されました.
高い温度下でも精密なT(3/2) 粘度スケーリングが観察されました.
シーア粘度とエントロピー密度の比率を推定し,完璧な流体の理論的予測と比較した.

結論:

実験的な測定は,フェルミガスにおける普遍的な水力学理論を支持する.
この研究は,剪定粘度とその温度依存性に関する定量的なデータを提供します.
発見は,強く相互作用するシステムにおける輸送特性の量子的性質を理解するのに寄与する.

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