title: Atom number in magneto-optic traps with millimeter scale laser beams.
abstract: We measure the number of atoms N trapped in a conventional vapor-cell magneto-optic trap (MOT) using beams that have a diameter d in the range 1-5 mm. We show that the N is proportional to d(3.6) scaling law observed for larger MOTs is a robust approximation for optimized MOTs with beam diameters as small as 3 mm. For smaller beams, the description of the scaling depends on how d is defined. The most consistent picture of the scaling is obtained when d is defined as the diameter where the intensity profile of the trapping beams decreases to the saturation intensity. Using this definition, N scales as d(6) for d<2.3 mm but, at larger d, N still scales as d(3.6).
authors: National Institute of Standards and Technology, Boulder, Colorado 80305, USA.
authors: Gregory W
authors: GW
authors: Hoth
authors: Elizabeth A
authors: EA
authors: Donley
authors: John
authors: J
authors: Kitching