Pair fraction in a finite temperature Fermi gas on the BEC side of the BCS-BEC crossover

Abstract

We investigate pairing in a strongly interacting two-component Fermi gas with positive scattering length. In this regime, pairing occurs at temperatures above the superfluid critical temperature; unbound fermions and pairs coexist in thermal equilibrium. Measuring the total number of these fermion pairs in the gas we systematically investigate the phases in the sectors of pseudogap and preformed-pair. Our measurements quantitatively test predictions from two theoretical models. Interestingly, we find that already a model based on classical atom-molecule equilibrium describes our data quite well.

arXiv comment6 pages, 5 figures

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Cited by in corpus (9)

• Superfluid signatures in a dissipative quantum point contact
• Universal pair-polaritons in a strongly interacting Fermi gas
• Solution of the BEC to BCS Quench in One Dimension
• Pair correlations in the normal phase of an attractive Fermi gas
• Photo-excitation measurement of Tan's contact for a strongly interacting Fermi gas
• Ground states of atomic Fermi gases in a two-dimensional optical lattice with and without population imbalance
• Spin-dipole mode in a trapped Fermi gas near unitarity
• Probing pair correlations in Fermi gases with Ramsey-Bragg interferometry
• Dimer-projection contact and the clock shift of a unitary Fermi gas