Multi-axis inertial sensing with 2D arrays of matter waves

Atom interferometery is an exquisite measurement technique sensitive to inertial forces. However, it is commonly limited to a single sensitive axis, allowing high-precision multi-dimensional sensing only through subsequent or post-corrected measurements. We report on a novel method for multi-axis inertial sensing based on the correlation of simultaneous light-pulse atom interferometers in 2D array arrangements of Bose-Einstein Condensates (BEC). Deploying a scalable 3 x 3 BEC array spanning 1.6 mm^2 created using time-averaged optical potentials, we perform measurements of linear acceleration induced by gravity and simultaneously demonstrate sensitivity to angular velocity and acceleration of a rotating reference mirror, as well as gravity gradients and higher-order derivatives. Our work enables simple, high-precision multi-axis inertial sensing compatible with high rotation rates, e.g., for inertial navigation in dynamic environments. We finally envision further applications of our method, e.g., 3D in-situ measurements and reconstruction of laser beam intensities and wave fronts.