Large atom number Bose-Einstein condensate of sodium
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.
Cite
@article{arxiv.physics/0609028,
title = {Large atom number Bose-Einstein condensate of sodium},
author = {K. M. R. van der Stam and E. D. van Ooijen and R. Meppelink and J. M. Vogels and P. van der Straten},
journal= {arXiv preprint arXiv:physics/0609028},
year = {2009}
}
Comments
11 pages, 12 figures, submitted to Review Of Scientific Instruments