Atom interferometric gravity data acquisition with the transportable absolute Quantum Gravimeter QG-1*

The transportable Quantum Gravimeter QG-1 derives the local gravity value from the interferometric signal of magnetically collimated Bose-Einstein condensates (BECs) released into free-fall and read out by absorption imaging. It aims to determine the gravity value with an uncertainty < 3 nm/s^2, an order of magnitude below the uncertainty of cold atom gravimeteres [1-3]. The minimized initial velocity and expansion rate of the collimated BEC, produced with our atom-chip-based source, enables the projected increase in accuracy. Employing BECs allows to drive high contrast interferometers with higher order Bargg transitions increasing the interferometer sensitivity. A BEC sample gives rise to additional systematic effects i.e. phase shifts driven by the mean field energy. Further the atom chip induces shifts stemming from black-body radiation. We discuss these effects and introduce the overall setup.

(1) C. Freier et al., J. Phys. Conf. Ser. 723

(2) R. Karcher,  et al., New J. Phys 20.11

(3) A. Louchet-Chauvet et al., New J. Phys. 13