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arXiv · 0805.0623

Realization of a strongly interacting Bose-Fermi mixture from a two-component Fermi gas

Yong-il Shin·André Schirotzek·Christian H. Schunck·Wolfgang Ketterle
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Abstract

We show the emergence of a strongly interacting Bose-Fermi mixture from a two-component Fermi mixture with population imbalance. By analyzing in situ density profiles of $^6$Li atoms in the BCS-BEC crossover regime we identify a critical interaction strength, beyond which all minority atoms pair up with majority atoms, and form a Bose condensate. This is the regime where the system can be effectively described as a boson-fermion mixture. We determine the dimer-fermion and dimer-dimer scattering lengths and beyond-mean-field contributions. Our study realizes a Gedanken experiment of bosons immersed in a Fermi sea of one of their constituents, revealing the composite nature of the bosons.

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Yong-il Shin, André Schirotzek, Christian H. Schunck, Wolfgang Ketterle. 2008-05-06. Realization of a strongly interacting Bose-Fermi mixture from a two-component Fermi gas. https://doi.org/10.1103/physrevlett.101.070404

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