Multiply Loaded, ac Magnetic Trap for Neutral Atoms

Harold J. Metcalf, P. van der Straten

Eric Cornell, Chris Monroe, Carl Wieman

We have demonstrated an oscillating-gradient magnetic trap for confining cesium atoms in the lowest-energy spin state. In this state spin-flip collisions are energetically forbidden and thus the primary density- and temperature-limiting process for magnetic traps is eliminated. The atoms are initially collected in a vapor-cell optical trap, then repetitively tossed into a high-vacuum region, focused in three dimensions, and accumulated in the magnetic trap. An optical pumping scheme inserts each new batch of atoms into the magnetic trap without perturbing the atoms already trapped.

Xu Li-Fang

In this article, a novel ac electro-magnetic trap for neutral atoms is proposed, which is based on the interaction of a magnetic dipole moment of trapped atoms with both an ac quadruple magnetic field in the transverse direction and a dc-bias magnetic field along the axial direction. The result shows that this is an ideal strong field-seeking trap for cold atoms. An atom guide with radial trapping potential over 1.2 mK is obtained and the guided atoms can be confined in a small region of r～50 μm. With changing the distribution of the bias magnetic field, an ac magneitc trap of cold atoms with axial potential depth 0.5 mK and radial potential 0.6 mK can be got, which is high enough to trap nearly all atoms with a temperature of ～120 μK.

Mukund Vengalattore, Mara Goff Prentiss

David C. Aveline, Robert J. Thompson, Nathan E. Lundblad +3 more

We describe a method of efficiently loading and manipulating neutral atoms in atom chip traps. Cooled87Rb from a MOT is transported via coil-based magnetic traps into chip-based wire traps and precisely directed in wire-guides.

Bruno Desruelle, Vincent Boyer, S. Murdoch +5 more