Progress toward a Raman-Ramsey Clock Based on a Transverse Cooled Rubidium Beam

SummaryIn this paper we reported our progress toward an atomic beam clock based on a transverse cooled rubidium beam. The atomic beam is generated from an atomic oven and collimated via micro-channel arrays and a two-dimensional optical lattice. After optical pumping, the rubidium beam interacts with two spatially separated Raman beams with a π/2 − π/2 sequence. High contrast Raman-Ramsey fringes are observed by using fluorescence detection. Preliminary result shows that the estimated frequency stability of the atomic clock reaches $2.6 \times {10^{ - 11}}/\sqrt \tau $. The atomic beam clock is proposed as a part of atomic beam inertial navigation unit for field applications.