Single-Photon Atomic Cooling - Raizen Lab - The University of ...

sublevels.
The increase in phase-space density demonstrated here is limited by
technical constraints and does not represent a fundamental limit to this pro-
cess. In the next section an improved version of the experiment is presented in
which the atomic transfer efficiency is limited only by the dynamics of atoms
in the magnetic trap.
4.4 “Optical Trough” Configuration
This section discusses the third, and current, experimental iteration of
the single-photon cooling process [96]. As will be discussed in this section,
the transfer efficiency of this iteration of the experiment is limited only by the
dynamics of the atoms in the magnetic trap. In other words, all atoms which
reach the depopulation beam with an energy less than the optical trap depth
are cooled and transfered into the optical trap via the single-photon cooling
process. The major changes made in this iteration were in the construction and
placement of the optical dipole trap and the method of introducing magnet-
ically trapped atoms into the depopulation beam near their classical turning
points. Both of these improvements are discussed in more detail below. To-
gether these changes resulted in a system performance increase of a factor of
15.
As in the previous two iterations, atoms were initially loaded into a
MOT, cooled with optical molasses, optically pumped, and then transfered
into the magnetic trap. While we were able to vary both the number NB and
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