STAGE Realization and characterization of a slow and intense source of Ytterbium for atom interferometry

Light-pulse atom interferometry, where light pulses are used to coherently split and recombine atom wave-packets, has led to extremely sensitive and accurate inertial sensors that can be used to perform very stringent tests of fundamental physics such as: testing the equivalence principle, detecting gravitational waves, probing short-range forces or measuring fundamental constants (e.g. Newton’s gravitational constant or the fine-structure constant). Usually, these quantum sensors use mainly two-photon transitions on alkaline atoms (rubidium, cesium, ...). However, some of the most demanding applications in fundamental physics, such as the detection of gravitational waves or the search for a dark matter signature, require a substantial gain in sensitivity. One solution is to perform atomic diffraction using 1-photon transitions to metastable levels (optical clock transitions), which would reduce laser phase noise. Alkaline earth or rare earth atoms (strontium, ytterbium, calcium, ...), which have already been used to make optical clocks, are very good candidates.

The atom interferometry team at LKB is currently designing and building a new experimental setup to trap and laser-cool ytterbium (Yb) atoms for i) developing new advanced tools for atom interferometry based on continuous-wave as well as on frequency-comb lasers and ii) in the long term, measuring by atom interferometry the recoil of Yb atoms upon absorption or emission of photons. Importantly, this measurement would provide a new and independent determination of the fine-structure constant for a stringent test of the Standard Model.