A Preliminary Measurement of h/mRb using Ultracold Atoms

We use Bloch oscillations in a horizontal and a vertical moving standing wave to transfer a large number of photon recoils to atoms. By measuring the photon recoil of
⁸⁷
Rb using velocity selective Raman transitions to select a subrecoil velocity class and to measure the final accelerated velocity class, we have determined h/m
_Rb
with a relative precision of 0.4 ppm