Recent improvements on the atomic fountain clock at SIOM*
Du Yuan-Boa),b), Wei Rong†a), Dong Ri-Changa),b), Zou Fana),b), Wang Yu-Zhua)
       
(a) The short-term frequency stability of the OCXO versus the H-maser for a given constant control voltage, which shows the control noise of the electronic circuit is reduced. Black square: previous value; red diamond: new result. (b) TOF signal of 87Rb cold atoms populated in | F = 1; m F = 0〉 (dashed line) and | F = 2; m F = 0〉 (solid line) detected in the probe region during the ballistic flight with the temperature of 2.0 μK. (c) The Ramsey fringe measured in the AFC, with the linewidth of 1 Hz and the SNR of 246.