Towards Microwave Shielding of NaCs Ground State Molecules

We report on microwave studies of ultracold ground state sodium-cesium (NaCs) molecules. We show spectroscopic data on microwave transitions to the first rotationally excited state and model our system with a Hamiltonian that allows us to assign quantum numbers and transition strengths. We observe fast Rabi oscillations between the ground and first rotationally excited states. We are working towards strong coupling with circularly polarized microwave radiation to enable microwave shielding against two-body losses. For NaCs, this may allow direct evaporation to a molecular Bose-Einstein condensate.