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Evaporative cooling of an atomic beam

E. Mandonnet·A. Minguzi·R. Dum·I. Carusotto·Y. Castin·J. Dalibard
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Abstract

We present a theoretical analysis of the evaporative cooling of an atomic beam propagating in a magnetic guide. Cooling is provided by transverse evaporation. The atomic dynamics inside the guide is analyzed by solving the Boltzmann equation with two different approaches: an approximate analytical ansatz and a Monte-Carlo simulation. Within their domain of validity, these two methods are found to be in very good agreement with each other. They allow us to determine how the phase-space density and the flux of the beam vary along its direction of propagation. We find a significant increase for the phase-space density along the guide for realistic experimental parameters. By extrapolation, we estimate the length of the beam needed to reach quantum degeneracy.

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E. Mandonnet, A. Minguzi, R. Dum, I. Carusotto, Y. Castin, J. Dalibard. 1999-11-16. Evaporative cooling of an atomic beam. https://doi.org/10.1007/s100530050521

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