Stable DFB Ridge Laser Diodes at 894nm at R.T. for Cesium Atomic Clocks

Time & Frequency applications concern the definition of a universal time, the synchronization of modern telecommunication systems, fundamental physics experiments, the communications with and between satellites, including Global Navigation Satellite System (GPS, Glonass, Galileo). These applications need high accuracy and high stability atomic clocks. Optically pumped compact industrial Cesium atomic clocks are a promising approach to satisfy these demands ([1]). To achieve atomic preparation and interrogation, one can consider the transition lines between the ground state 6
²
S
_1/2
and the two following excited states of the fine structure of Cesium: 6
²
P
_1/2
(D1 line around 894nm) and 6
²
P
_3/2
(D2 line around 852nm). The use of D1 line for pumping should provide simplified clock architecture compared to the D2 line pumping thanks to simpler atomic transitions and a larger spectral separation between lines in the 894 nm case ([2]).