Why only half of the fermionic atoms were converted to molecules by a Feshbach resonance?

Hui Hu; Feng Yuan; Shaojin Qin

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Why only half of the fermionic atoms were converted to molecules by a Feshbach resonance?

Hui Hu·Feng Yuan·Shaojin Qin

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Abstract

In some recent experiments an ultracold gas of $^{40}$K$_2$ (or $^{6}$Li$_2$) molecules has been produced from a degenerate two-component Fermi gas of $^{40}$K (or $^{6}$Li) atoms by adiabatic passage through a Feshbach resonance. The maximum atom-molecule transfer efficiency is reported to be about 50%. We propose a simple microscopic model to characterize the ground state of the gas in the vicinity of the resonance, and show that the term describing the atom-molecule coupling is responsible for the observed efficiency 50%. Our result also suggests that the experiments have produced a molecular condensate.

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Hui Hu, Feng Yuan, Shaojin Qin. 2003-08-24. Why only half of the fermionic atoms were converted to molecules by a Feshbach resonance?. https://arxiv.org/abs/cond-mat/0308474

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