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arXiv · 1006.3250

Observation of collective atomic recoil motion in a momentum-squeezed, ultra-cold, degenerate fermion gas

Pengjun Wang·L. Deng·E. W. Hagley·Zhengkun Fu·Shijie Chai·Jing Zhang
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Abstract

We demonstrate clear collective atomic recoil motion in a dilute, momentum-squeezed, ultra-cold degenerate fermion gas by circumventing the effects of Pauli blocking. Although gain from bosonic stimulation is necessarily absent because the quantum gas obeys Fermi-Dirac statistics, collective atomic recoil motion from the underlying wave-mixing process is clearly visible. With a single pump pulse of the proper polarization, we observe two mutually-perpendicular wave-mixing processes occurring simultaneously. Our experiments also indicate that the red-blue pump detuning asymmetry observed with Bose-Einstein condensates does not occur with fermions.

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Pengjun Wang, L. Deng, E. W. Hagley, Zhengkun Fu, Shijie Chai, Jing Zhang. 2010-06-17. Observation of collective atomic recoil motion in a momentum-squeezed, ultra-cold, degenerate fermion gas. https://doi.org/10.1103/physrevlett.106.210401

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