Towards trapped atom interferometry for quantum inertial sensing: Creating, shaping and manipulating BECs

Position determination for the purpose of navigation plays a crucial role for modern civilization. However, the use of global satellite systems in conjunction with classical inertial sensors has severe limitations due to restricted availability and error accumulation. Trapped atom interferometers are promising candidates for new devices addressing these problems, as they aim to combine the robustness of classical sensors with the precision of light-pulse atom interferometers.

We report on our progress towards such systems in which we realize Bose-Einstein condensation and atom optical operations in an optical waveguide. Using time-averaged optical dipole potentials to create and shape our trap, we show coherent splitting and recombination of our atomic ensemble by tunnelling and combinations thereof with Bragg beam splitting. Beyond demonstrations with ⁸⁷Rb, we also implement ³⁹K. By tuning its scattering length with a magnetic Feshbach resonance we decrease our evaporation time by a factor of 5 to 850 ms, while doubling the atomic flux. We discuss additional applications of our setup for matter wave lensing, showing a reduction in expansion temperature by an order of magnitude with possible applications in free falling inertial sensitive atom interferometers.