Short-range correlations and entropy in ultracold atomic Fermi gases

Abstract

We relate short-range correlations in ultracold atomic Fermi gases to the entropy of the system over the entire temperature, $T$, vs. coupling strength, $-1/k_{F}a$, plane. In the low temperature limit the entropy is dominated by phonon excitations and the correlations increase as $T^4$. In the BEC limit, we calculate a boson model within the Bogoliubov approximation to show explicitly how phonons enhance the fermion correlations. In the high temperature limit, we show from the virial expansion that the correlations decrease as $1/T$. The correlations therefore reach a maximum at a finite temperature. We infer the general structure of the isentropes of the Fermi gas in the $T,-1/k_{F}a$ plane, and the temperature dependence of the correlations in the unitary, BEC, and BCS limits. Our results compare well with measurements of the correlations via photoassociation experiments at higher temperatures.

6 pages, 3 figures

References in corpus (16)

• Large momentum part of fermions with large scattering length
• Energetics of a strongly correlated Fermi gas
• Weakly bound dimers of fermionic atoms
• Equation of state of a Fermi gas in the BEC-BCS crossover: a quantum Monte Carlo study
• Molecular Probe of Pairing in the BEC-BCS Crossover
• Exact Relations for a Strongly-interacting Fermi Gas from the Operator Product Expansion
• The transition temperature of the dilute interacting Bose gas
• Collective mode of homogeneous superfluid Fermi gases in the BEC-BCS crossover
• Number of closed-channel molecules in the BEC-BCS crossover
• Universal Properties of the Ultra-Cold Fermi Gas
• High temperature expansion applied to fermions near Feshbach resonance
• Theory of RF-spectroscopy of strongly interacting Fermions
• Thermodynamic Measurements in a Strongly Interacting Fermi Gas
• Critical Temperature Curve in the BEC-BCS Crossover
• Coherence and clock shifts in ultracold Fermi gases with resonant interactions
• Pair correlations of an expanding superfluid Fermi gas

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