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arXiv · 1004.1465

The Equation of State of a Low-Temperature Fermi Gas with Tunable Interactions

Nir Navon·Sylvain Nascimbène·Frédéric Chevy·Christophe Salomon
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Abstract

Interacting fermions are ubiquitous in nature and understanding their thermodynamics is an important problem. We measure the equation of state of a two-component ultracold Fermi gas for a wide range of interaction strengths at low temperature. A detailed comparison with theories including Monte-Carlo calculations and the Lee-Huang-Yang corrections for low-density bosonic and fermionic superfluids is presented. The low-temperature phase diagram of the spin imbalanced gas reveals Fermi liquid behavior of the partially polarized normal phase for all but the weakest interactions. Our results provide a benchmark for many-body theories and are relevant to other fermionic systems such as the crust of neutron stars.

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Nir Navon, Sylvain Nascimbène, Frédéric Chevy, Christophe Salomon. 2010-04-09. The Equation of State of a Low-Temperature Fermi Gas with Tunable Interactions. https://doi.org/10.1126/science.1187582

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