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

μ
μ
μ
Figure 4.18: Side view of the optical trough potential displaying the trap
depth.
the ‘V’.
One further change made during this iteration was that we placed the
optical trough below the magnetically trapped atoms in contrast to the last
section in which the optical box was placed above the magnetic trap. Placing
the trough below the magnetically trapped atoms is a more favorable geometry
because atoms do not have to climb an optical potential hill to enter the optical
trap. This is clearly advantageous for this cooling process because atoms
climbing a potential hill subsequently fall down it, increasing their kinetic
energy in the process. This places a lower limit on the final temperature of
the sample.
As described in the previous two sections, the depopulation beam drives
atoms from the |F = 2,mF = 2〉 state into the 5 2 S1/2(F = 1) manifold. It
does this by exciting them into the |F ′ = 1,m ′ F
161
= 1〉 state from where they