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Theory of Feshbach molecule formation in a dilute gas during a magnetic field ramp

J. E. Williams·N. Nygaard·C. W. Clark
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Abstract

Starting with coupled atom-molecule Boltzmann equations, we develop a simplified model to understand molecule formation observed in recent experiments. Our theory predicts several key features: (1) the effective adiabatic rate constant is proportional to density; (2) in an adiabatic ramp, the dependence of molecular fraction on magnetic field resembles an error function whose width and centroid are related to the temperature; (3) the molecular production efficiency is a universal function of the initial phase space density, the specific form of which we derive for a classical gas. Our predictions show qualitative agreement with the data from [Hodby et al, Phys. Rev. Lett. {\bf{94}}, 120402 (2005)] without the use of adjustable parameters.

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J. E. Williams, N. Nygaard, C. W. Clark. 2005-11-01. Theory of Feshbach molecule formation in a dilute gas during a magnetic field ramp. https://doi.org/10.1088/1367-2630%2F8%2F8%2F150

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