Sensitive gravity-gradiometry with atom interferometry: progress towards an improved determination of the gravitational constant

Abstract

We here present a high sensitivity gravity-gradiometer based on atom\ninterferometry. In our apparatus, two clouds of laser-cooled rubidium atoms are\nlaunched in fountain configuration and interrogated by a Raman interferometry\nsequence to probe the gradient of gravity field. We recently implemented a\nhigh-flux atomic source and a newly designed Raman lasers system in the\ninstrument set-up. We discuss the applications towards a precise determination\nof the Newtonian gravitational constant G. The long-term stability of the\ninstrument and the signal-to-noise ratio demonstrated here open interesting\nperspectives for pushing the measurement precision below the 100 ppm level.\n