Observatoire de Neuchâtel has developed a compact opticallypumped cesium beam frequency standard in the frame of an ESA-ARTES 5 project. The simplest optical scheme, which is based on a single optical frequency for both preparation and detection processes of atoms, has been chosen to fulfill reliability constraints of space applications. With the last evolution of our laboratory demonstrator, we have measured a frequency stability of σ σ σ σ y =1.14x10 -12 τ τ τ τ -1/2 , which is compliant with the Galileo requirement and our frequency stability goal of σ σ σ σ y =1x10 -12 τ τ τ τ -1/2 . Present performance limitations are discussed and further improvements are proposed to possibly increase the frequency stability.

Performance demonstration of a single-frequency opticallypumped cesium beam frequency standard for space applications S. Lecomte, M. Haldimann, R. Ruffieux, P. Thomann, et , which is compliant with the Galileo requirement. The atomic resonator is fully compliant to be operated with a single diode laser at 894 nm (D 1 line). Sensitivity measurements of the clock signal to the microwave power and to the optical pumping power are also presented. Present performance limitations are discussed and further improvements are proposed in order to reach our ultimate frequency stability goal of y =1x10 -12 -1/2 . The clock driving software is also briefly described.

No abstract