Testing Atom Neutrality with Atom Interferometry – TANAI

Nowadays, atom interferometers are implemented as precision sensors in multiple research areas. This technology demonstrated inertial sensors comparable with the best commercial sensors and is becoming a serious alternative for gravity measurements and geophysics applications. They participate to the measurements of fundamental constants such as the gravitational constant or the fine-structure constant. In fundamental physics, they are expected for testing general relativity, QED and new models in particle physics.

This ANR project contributes to the study of new techniques in order to overcome the current limitations of atom interferometers. The project is based on an atom interferometer working at the state of the art level and proposes a test of the atom neutrality using a new approach based on geometrical phase shifts.

At first we will develop a new interferometer based on Bose-Einstein Condensates (BEC) and Optical Lattices (OL) to create a large separation between the two interfering paths. This experiment will contribute to study systematic and noise effects at a great accuracy level. In addition, we will study more advanced techniques relevant for the atom interferometers and their metrological gain. In particular, we plan to implement optimal control methods, to improve the performances and the robustness of interferometers using BEC and optical lattices.

Beyond this development in quantum engineering, we will apply our new atom interferometer to push further the limit of the electrical neutrality of matter. Precisely testing the electrical neutrality of matter is highly significant in the extension of the standard model, for electrical metrology and it is also interesting in cosmology. Despite many experimental efforts made in the past few decades, the improvements are relatively small. We propose a completely new method based on the scalar Aharonov-Bohm geometrical phase shift to improve the current laboratory limits by 2 orders of magnitude.

TANAI will contribute to advance atom interferometry, to push the sensitivity of quantum sensors to new levels. The techniques studied in TANAI are of great interest for the developments of future on-board inertial sensors, as well as for the development of more ambitious programs planned in the next decade (gravitational detectors, space missions, etc.). Indeed, some of the methods tested during the project are part of their scientific and technological prerequisites. Industrial partners could be involved to further develop the technology. Finally, the new apparatus opens new possibilities for exploring the use of geometrical phases in metrology. Therefore, this project will allow a young researcher to develop his own research field that will be complementary to the research being led in the atom interferometry teams.