Realization and characterization of a continuous-wave atom laser

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We have constructed a Zeeman slower of rubidium atoms which produces a slow atomic beam with a velocity of about 20 m/s. We loaded a magneto-optical trap with this slow atomic beam, resulting in a large number of cold atomic sample (about 10^10. We then trap this atomic sample with a quadrupole magnetic field which was produced by an anti-Helmholtz coil. Furthermore. With the help of another anti-Helmholtz coil, which has a different trap center, we shifted the atomic sample close to the glass surface adiabatically. As the hotter atoms selectively collide with the surface, evaporative cooling works, and the phase space density was increased by a factor of 2. To demonstrate a much larger enhancement in the phase space density, we tried to transfer the atomic sample in a quadrupole magnetic field to an Ioffe-Pritchard magnetic field which is produced by a Z-shaped wire, and adiabatically compress the atomic sample. However, the transfer efficiency was as low as 10 %, therefore we could not achieve a density high enough to perform evaporative cooling, In the future, we want to transfer the atom, captured in a MOT directly to an Ioffe-Pritchard magnetic trap, adiabatically compress, and perform evaporative cooling near the grass surface. We published a paper on the techniques of producing a high-intensity ultra-cold atomic beam (Rev. Sci. Instrum. 77, 023106(2006)) as a result of a cooperative research with MIT.