Vector Atom Accelerometry in an Optical Lattice

We experimentally demonstrate two multidimensional atom interferometers capable of measuring both the magnitude and direction of applied inertial forces. These interferometers do not rely on the ubiquitous light-pulses of traditional atom sensors, but are instead built from an innovative design that operates entirely within the Bloch bands of an optical lattice formed by interfering laser beams. Through time-dependent control of the position of the lattice in three-dimensional space, we realize simultaneous Bloch oscillations in two dimensions, and a vector atomic Michelson interferometer. Fits to the observed Bloch oscillations demonstrate the measurement of an applied acceleration of 2g along two axes, where g is the average gravitational acceleration at the Earth's surface. For the Michelson interferometer, we perform Bayesian inferencing from a 49-channel output by repeating experiments for selected examples of two-axis accelerations. We demonstrate the resulting accuracy and sensitivity for vector parameter estimation. Our acceleration can be measured from a single experimental run and does not require repeated shots to construct a fringe. We find the performance of our device to be near the quantum limit for the interferometer size and quantum detection efficiency of the atoms. We discuss the reconfigurability of the vector accelerometer and the pathway toward further sensitivity.