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arXiv · 0801.1523

Determination of the Equation of State of a Two-Component Fermi Gas at Unitarity

Yong-il Shin
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Abstract

We report on the measurement of the equation of state of a two-component Fermi gas of $^6$Li atoms with resonant interactions. By analyzing the \textit{in situ} density distributions of a population-imbalanced Fermi mixture reported in the recent experiment [Y. Shin \textit{et al.}, Nature \textbf{451}, 689 (2008)], we determine the energy density of a resonantly interacting Fermi gas as a function of the densities of the two components. We present a method to determine the equation of state directly from the shape of the trapped cloud, where the fully-polarized, non-interacting ideal Fermi gas in the outer region provides the absolute calibration of particle density. From the density profiles obtained at the lowest temperature, we estimate the zero-temperature equation of state.

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Yong-il Shin. 2008-03-28. Determination of the Equation of State of a Two-Component Fermi Gas at Unitarity. https://doi.org/10.1103/physreva.77.041603

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