Towards Multidimensional Inertial Sensing using Bloch-Band Interferometry

We present recent advances in Bloch-band interferometry (BBI), a programmable sensing technique that employs Bose-Einstein condensate atoms in an optical lattice and exploits the lattice band structure to implement interferometric operations. BBI has previously demonstrated inertial sensing in one and two dimensions [1,2] and enabled a universal set of atom-optic components for measuring rotations and multiple components of the gravity-gradient tensor [3]. This work reports progress on two technical developments critical for improving BBI sensitivity. First, we demonstrate an optical lattice phase controller that suppresses lattice phase noise while providing high-bandwidth phase modulation, enabling faithful implementation of machine-learned BBI protocols [4]. Second, we explore BBI operation in a large dynamically painted optical trap with a calibrated intensity gradient that provides an optical buoyancy potential and compensates gravitational acceleration. This configuration enables interferometry in a sub-milli-g environment and allows atomic wavepacket splitting over hundreds of microns while remaining confined to the optical lattice. These developments enhance the sensitivity of BBI sequences and advance the prospects for precise, multidimensional inertial sensing in this platform.