Aging study on a micro-fabricated Cs buffer-gas cell for atomic clock applications

We present an aging study on Cs micro cells for chip scale miniature atomic clocks. We observe a temporal evolution of the intrinsic clock transition frequency and compare it to the frequency variations of the clock transition induced by different physical effects for gas cell atomic clocks. The measured cell frequency drift is found to be comparable with a slow reduction of the buffer gas pressure inside the cell. These studies are of relevance for the development of miniature atomic clocks for precision time keeping and portable applications.