ハンベリー・ブラウン・トウィス効果は,超冷たい量子ガスのためのものです

M Schellekens¹, R Hoppeler, A Perrin

¹Laboratoire Charles Fabry de l'Institut d'Optique, UMR 8501 du CNRS, Centre Scientifique d'Orsay, Bâtiment 503, 91403 Orsay CEDEX, France.

Science (New York, N.Y.)

|September 17, 2005

まとめ

我々は,ハンベリー・ブラウン・ツィス効果に似た,原子のボース・アインシュタイン凝縮体における量子相関を観察した. 熱雲は粒子の束を表示し,一貫したサンプルは平らな相関を示します.

科学分野:

原子物理学原子物理学とは
量子光学とは,量子光学である.
凝縮物質物理学凝縮物質物理学

背景:

ボーゼ・アインシュタイン凝縮 (Bose-Einstein condensation,BEC) とは,物質の量子状態である.
二体相関は,粒子の量子統計的性質を明らかにする.
ハンベリー・ブラウン・トゥイス (HBT) 効果は,量子光学における光子相関を証明している.

研究の目的:

BEC値に近い原子雲の2体相関を調査する.
ハンベリー・ブラウン・トゥイス効果の原子類似性を探求する.
量子相関が雲の大きさと相関性に依存しているかを分析する.

主な方法:

膨張する原子雲をBEC値の上下に研究した.
三次元で測定された二体相関関数.
熱的および一貫した原子サンプルのための相関関数の比較.

主要な成果:

熱原子雲の相関関数における観察された束の挙動.
一貫した原子サンプルに対して平らな相関関数が見つかりました.
ハンベリー・ブラウン・トゥイス効果の原子類似性を実証した.

結論:

量子相関は,熱的サンプルと一貫した原子サンプルの間に著しく異なる.
観測された原子相関は,HBT効果と一致しています.
雲の大きさは,これらの量子相関の現れに影響する.

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