Atom interferometry using Floquet-Bloch band engineering*

Conventional free-space atom interferometers rely on large free-fall distances to achieve high sensitivity, posing challenges for portability and local force measurements. We present a novel atom interferometer using non-interacting Bose-Einstein condensates confined in an optical lattice. Leveraging Floquet control, we demonstrate precise splitting and recombination of matter waves across distinct Bloch bands. To mitigate trapping dephasing, we operate the interferometer with a magic band structure. As a proof of concept, we perform a force measurement based on the interference fringe between two Bloch bands, showcasing the potential of this method for high-precision local sensing.