Fast production of large 23Na Bose-Einstein condensates in an optically plugged magnetic quadrupole trap

摘要

We demonstrate a fast production of large 23Na Bose-Einstein condensates inan optically plugged, magnetic quadrupole trap. A single global minimum of thetrapping potential is generated by slightly displacing the plug beam from thecenter of the quadrupole field. With a dark magneto-optical trap and a simplerf evaporation, our system produces a condensate with N = 10^7 atoms every 17s. The Majorana loss rates and the resultant heating rates for varioustemperatures are measured with and without plugging. The average energy of aspin-flipped atom is almost linearly proportional to temperature and determinedto be about 60% of the average energy of a trapped atom. We present a numericalstudy of the evaporation dynamics in a plugged linear trap.