The Pauli exclusion principle forbids indistinguishable fermions from occupying the same quantum mechanical state. The implications of this are profound; for example, it accounts for the electronic shell structure of atoms. Here, we performed measurements on the scattering of light from ultracold ensembles of atoms. For a Fermi gas in the quantum degenerate regime, we observed a marked suppression in scattering compared with a similarly prepared Bose gas. The observed decrease in fluorescence and the corresponding increase in light transmission results from Pauli blocking, where Fermi-Dirac statistics limits the number of accessible states for a scattering atom in a large Fermi sea. Our work confirms a fundamental result on the optical response of quantum gases and may contribute to cooling and thermometry schemes.

中文翻译：

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量子简并费米子光散射中泡利阻塞的观察

泡利不相容原理禁止无法区分的费米子占据相同的量子力学状态。其影响是深远的。例如，它解释了原子的电子壳层结构。在这里，我们对来自超冷原子集合的光散射进行了测量。对于量子简并状态下的费米气体，我们观察到与类似制备的玻色气体相比，散射明显受到抑制。观察到的荧光减少和光传输的相应增加是泡利阻塞的结果，其中费米-狄拉克统计限制了大费米海中散射原子的可访问状态的数量。我们的工作证实了量子气体光学响应的​​基本结果，并可能有助于冷却和测温方案。