Accelerometry via reflective atom interferometry

We present a reflective atom-interferometric approach to acceleration sensing, in which matter waves are coherently split and recombined solely through diffraction from nanostructured surfaces. Unlike light-pulse atom interferometers, the method is completely laser-free and operates on millisecond time scales, enabling compact and robust sensor architectures. Two readout strategies are explored: (i) the shift of the diffracted output angles, and (ii) the interferometric phase modulation generated by three successive reflections within the device. Using analytical models for diffraction from a moving lattice, we compute the sensitivity to lateral and normal accelerations. The interferometric mode exhibits a pronounced amplification of small velocity changes, reaching sensitivities as low as 10⁻¹⁰\,g 10 - 10 g for slow atoms and large incidence angles. The response is intrinsically stronger for lateral than for normal accelerations due to the asymmetry of the diffraction paths. Comparisons with existing technologies show that the reflective interferometer fills a gap between MEMS-based accelerometers and large light-pulse atom interferometers, offering high sensitivity, continuous readout, and a fully passive beam-splitting mechanism. These results identify reflective interferometry as a promising platform for next-generation quantum accelerometers.