Continuous, Velocity-Controlled Three-Dimensionally Laser-Cooled Atom Beam Source with Low Fluorescence

An apparatus for forming a continuous, velocity-controlled three-dimensionally laser-cooled atom beam, comprising:

• a two-stage vacuum enclosure comprising a first laser-cooling region and a second laser-cooling region joined to the first laser-cooling region via an intermediate region that is opaque to a wavelength of laser beams in the first laser-cooling region, the intermediate region having an aperture formed therein to join with the second laser-cooling region, a longitudinal axis of the second laser-cooling region being offset from a longitudinal axis of the first laser-cooing region;
• the first laser-cooling region including at least one magnetic element configured to apply a magnetic field to atoms in the first laser-cooling region;
• first laser sources that direct a first set of counterpropagating laser beams comprising two beams offset from one another by a predetermined angle into atoms in the first laser-cooling region in the presence of the magnetic field, the first set of counterpropagating beams and the magnetic field forming a two-dimensional magneto-optical trap (2D+ MOT) that transversely cools the atoms in the first laser-cooling region and causes them to form an atom beam that travels into the second laser-cooling region via the aperture;
• and
• second laser sources that apply a second set of counterpropagating laser beams to the atom beam in the second laser-cooling region, the second set of counterpropagating laser beams comprising a first pair of counterpropagating beams traveling along a z+/z− axis and further comprising a second and third pair of counterpropagating beams propagating in an x-y plane, the second and third pair of counterpropagating beams being separated from one another by a second predetermined angle, the second set of counterpropagating laser beams forming a three-dimensional optical molasses (3D OM) in the second laser-cooling region;
• wherein the first set of beams forming the 2D+ MOT and the second set of beams forming the 3D OM all are fired simultaneously and continuously as the atoms travel through the enclosure;
• wherein each of the beams forming the 2D+ MOT and each of the beams forming the 3D OM has a corresponding wavelength, the wavelength of each beam having a predetermined difference from a resonance frequency of the atoms in the atom vapor, all of the beams forming the 2D+ MOT and the 3D OM being fired simultaneously and continuously as the atoms travel through the enclosure;
• and
• wherein the 3D OM beams cool the initial transversely cooled atom beam in three dimensions to a predetermined sub-Doppler temperature and to a predetermined mean velocity as it travels through the second laser-cooling region to continuously produce a velocity-controlled three-dimensionally cooled low-fluorescence atom beam.