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Finite Temperature Momentum Distribution of a Trapped Fermi Gas

Qijin Chen·C. A. Regal·D. S. Jin·K. Levin
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Abstract

We present measurements of the temperature-dependent momentum distribution of a trapped Fermi gas consisting of $^{40}$K in the BCS-BEC crossover regime. Accompanying theoretical results based upon a simple mean-field ground state are compared to the experimental data. Non-monotonic effects associated with temperature, $T$, arise from the competition between thermal broadening and a narrowing of the distribution induced by the decrease in the excitation gap $Δ(T)$ with increasing $T$.

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Qijin Chen, C. A. Regal, D. S. Jin, K. Levin. 2006-04-20. Finite Temperature Momentum Distribution of a Trapped Fermi Gas. https://doi.org/10.1103/physreva.74.011601

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