Thermodynamics of a trapped unitary Fermi gas

Abstract

Thermodynamic properties of an ultracold Fermi gas in a harmonic trap are calculated within a local density approximation, using a conserving many-body formalism for the BCS to BEC crossover problem, which has been developed by Haussmann et al. [Phys. Rev. A 75, 023610 (2007)]. We focus on the unitary regime near a Feshbach resonance and determine the local density and entropy profiles and the global entropy S(E) as a function of the total energy E. Our results are in good agreement with both experimental data and previous analytical and numerical results for the thermodynamics of the unitary Fermi gas. The value of the Bertsch parameter at T=0 and the superfluid transition temperature, however, differ appreciably. We show that, well in the superfluid regime, removal of atoms near the cloud edge enables cooling far below temperatures that have been reached so far.

arXiv comment10 pages, 5 figures

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Cited by in corpus (32)

• Revealing the Superfluid Lambda Transition in the Universal Thermodynamics of a Unitary Fermi Gas
• Fermion Interactions and Universal Behavior in Strongly Interacting Theories
• The BCS-BEC crossover: From ultra-cold Fermi gases to nuclear systems
• Bragg spectroscopy of a strongly interacting Fermi gas
• Spectral Functions and rf Response of Ultracold Fermionic Atoms
• Thermodynamic Measurements in a Strongly Interacting Fermi Gas
• Two-Element Mixture of Bose and Fermi Superfluids
• Strongly correlated superfluid order parameters from dc Josephson supercurrents
• When Superconductivity Crosses Over: From BCS to BEC
• Universal thermodynamics of a strongly interacting Fermi gas: theory versus experiment
• Tunneling transport of unitary fermions across the superfluid transition
• Phase Diagram of a Strongly Interacting Spin-Imbalanced Fermi Gas
• Critical Behaviour in Trapped Strongly Interacting Fermi Gases
• Beyond-mean-field description of a trapped unitary Fermi gas with mass and population imbalance
• Quenches from gaussian bosons to Tonks-Girardeau gas: stationary states and effects of a confining potential
• Normal-Superfluid Interface for Polarized Fermion Gases
• Phonon contribution to the shear viscosity of a superfluid Fermi gas in the unitarity limit
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• Phases of spin- and mass-imbalanced ultracold Fermi gases in harmonic traps
• The finite-temperature thermodynamics of a trapped unitary Fermi gas within fractional exclusion statistics
• Pair correlations in the normal phase of an attractive Fermi gas
• Formation of magnetic impurities and pair-breaking effect in a superfluid Fermi gas
• Normal mass density of a superfluid Fermi gas at unitarity
• Finite temperature vortices in a rotating Fermi gas
• Unitary thermodynamics from thermodynamic geometry
• Spin susceptibility and effects of a harmonic trap in the BCS-BEC crossover regime of an ultracold Fermi gas
• Irreversible entropy transport enhanced by fermionic superfluidity
• Adiabatic cooling of a tunable Bose-Fermi mixture in an optical lattice
• Unitary thermodynamics from thermodynamic geometry II: Fit to a local density approximation
• Statistical mechanics of a Feshbach coupled Bose-Fermi gas in an optical lattice
• Triplet pair amplitude in a trapped $s$-wave superfluid Fermi gas with broken spin rotation symmetry. II. Three dimensional continuum case
• Cooling Quantum Gases with Entropy Localization