AGAPES

In recent years, the development of Atom Interferometry (AI) enabled multiple breakthroughs ranging from fundamental to applied physics, and led to the realization of a new class of quantum sensors offering unprecedented performances. In such experiments, the measurement sensitivity fundamentally depends on the separation of matter waves inside the interferometer, which is commonly limited by the use of 2-photon momentum transfer from the interrogation field to the atoms. To go further, original interferometry schemes have recently been demonstrated implementing “Large Momentum Transfer” (LMT) and multiplying the number of photons exchanged by factors up to a thousand. In spite of these major advances, precision measurements experiments based on AI are still strongly dominated by 2-photon beam splitting techniques. Through a strong French-German synergy, AGAPES will exploit the promising potential of LMT to boost the sensitivity of atom-interferometers-based sensors and open a new class of precision measurement experiments. Among a wide range of possible geometries, AGAPES will focus on the gradiometric configuration and develop novel cavity interrogation methods. This choice to embed the most convincing and promising configurations for LMT will ensure a quick and efficient implementation of LMT techniques for precision AI. To fulfill its ambitious goals, AGAPES will develop a new metrological framework to model and control noise sources and systematics effects of LMT interferometers. On this basis, AGAPES will demonstrate new applications of LMT interferometers for fundamental physics: in particular, it will provide new concepts based on cavity interrogation as baselines for future experiments exploring dark matter theories or detecting infrasound gravitational waves. AGAPES will also provide new tools to build advanced quantum sensors with applications in geoscience, geodesy, and space technologies: a major deliverable of the project will be the release of a complete simulation framework for high-precision gradiometry with LMT in free-space and cavity configurations. This tool will be realized in a modular way to ensure its use and future upgrade by a large community of users from fundamental and applied physics, as well as the private sector. AGAPES will benefit from the recognized experimental and theoretical expertise of the different partners in atom interferometry, quantum metrology and their applications. The work program will rely on the strong complementarity of the setups and background offered by the different partners, promising to study a wide span of the key experimental parameters and theoretical advances needed to efficiently implement LMT schemes. AGAPES will establish a new international team of excellence centered on precision AI. This partnership will not only tackle ambitious objectives to establish a new class of sensors but also fully contribute to the existing local research activities in both France and Germany.