Laser-pumped Rb clock for the space sector

We report the recent characterization of a Rb microwave clock based on pulsed laser pumping and detection. The laser pulses were generated by means of a mixed analog-digital controller that stabilizes the pulses amplitude and reduces the laser intensity noise (RIN). The physics package was developed by Leonardo S.p.A. using space-graded components, weighting less than 4 kg and occupying only a 4-liters volume.State-of-the-art short- and mid-term stability is obtained with this system, reaching σ
y
(40000s) = 5 × 10
⁻¹⁶
for a 200000 s run.