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.
Paintner T., Hoffmann D. K., Jäger M., Limmer W., Schoch W., Deissler B., et al. (2019). Pair fraction in a finite-temperature Fermi gas on the BEC side of the BCS-BEC crossover. PHYSICAL REVIEW A, 99(5), 053617-1-053617-5 [10.1103/PhysRevA.99.053617].
Pair fraction in a finite-temperature Fermi gas on the BEC side of the BCS-BEC crossover
Pieri P.;
2019
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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.