Infrasound gravitational wave detection with atoms

Atom interferometry offers an interesting perspective for the detection of gravitational waves in a frequency band between eLISA and Advanced LIGO, resulting in an active field of research. Ground based setups with vertical or horizontal baselines were considered, satellite missions investigated, and interferometer topologies developed. We investigate a novel geometry for a ground-based device combining several advantages as a horizontal baseline, enabling long baselines, a single axis laser link between the atom interferometers acting as phasemeters, and suppressing errors sources otherwise implying very strict requirements onto the atomic source. It is based on recent developments in symmetric beam splitters with scalable momentum transfer, relaunching techniques for suspending the atoms against gravity, and delta-kick collimation techniques to generate very slowly expanding atomic ensembles.