Multi-Axis Inertial Sensing with 2D Matter-Wave Arrays

Atom interferometery is an exquisite measurement technique sensitive to inertial forces. However, it is commonly limited to a single sensitive axis, allowing high-precision multidimensional sensing only through subsequent or postcorrected 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 3×3 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 Letter 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.