Short-range correlations and entropy in ultracold atomic Fermi gases

Understand

We relate short-range correlations in ultracold atomic Fermi gases to the entropy of the system over the entire temperature, $T$, vs.

• coupling strength, $-1/k_Fa$, 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.