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تسجيل مستخدم جديدUltracold Fermi gases in the BEC-BCS crossover: a review from the Innsbruck perspective
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تأليف
Rudolf Grimm
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A review of recent BEC-BCS crossover experiments in ultracold Fermi gases is given with particular emphasis on the work performed with lithium-6 at the University of Innsbruck.
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h resonance serves as the experimental key to tune the s-wave scattering length and thus to explore the various interaction regimes. In the BEC-BCS crossover, we have characterized the interaction energy by measuring the size of the trapped gas, we have studied collective excitation modes, and we have observed the pairing gap. Our observations provide strong evidence for superfluidity in the strongly interacting Fermi gas.
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alytic formula based on Monte Carlo data and the mean-field equation of state resulting from the extended BCS equations. The calculated axial and transverse radii and the aspect ratio of the expanding cloud are compared to experimental data on vapors of ^6Li atoms. Remarkably, the mean-field theory shows a better agreement with the experiments than the theory based on the Monte Carlo equation of state. Both theories predict a measurable dependence of the aspect ratio on expansion time and on scattering length.
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