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Large atom number Bose-Einstein condensate of sodium

K. M. R. van der Stam·E. D. van Ooijen·R. Meppelink·J. M. Vogels·P. van der Straten
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Abstract

We describe the setup to create a large Bose-Einstein condensate containing more than 120x10^6 atoms. In the experiment a thermal beam is slowed by a Zeeman slower and captured in a dark-spot magneto-optical trap (MOT). A typical dark-spot MOT in our experiments contains 2.0x10^10 atoms with a temperature of 320 microK and a density of about 1.0x10^11 atoms/cm^3. The sample is spin polarized in a high magnetic field, before the atoms are loaded in the magnetic trap. Spin polarizing in a high magnetic field results in an increase in the transfer efficiency by a factor of 2 compared to experiments without spin polarizing. In the magnetic trap the cloud is cooled to degeneracy in 50 s by evaporative cooling. To suppress the 3-body losses at the end of the evaporation the magnetic trap is decompressed in the axial direction.

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K. M. R. van der Stam, E. D. van Ooijen, R. Meppelink, J. M. Vogels, P. van der Straten. 2006-09-04. Large atom number Bose-Einstein condensate of sodium. https://doi.org/10.1063/1.2424439

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