Optical tweezer arrays of molecules from the bottom-up for quantum science

Ultracold molecules offer rich internal states and tunable long-range interactions that render them favorable for a wide range of quantum science applications. Towards this end, individual particle control over single molecules with long coherence times are desirable. In this talk, I will discuss our platform of molecular qubits, where optical tweezer arrays of NaCs molecules are created starting from individual Na and Cs atoms. This approach allows fine control over individual molecules, whilst also assuring molecules are in their internal and external ground states. Compared to other molecular qubit systems, NaCs has an exceptionally large differential light shift between qubit states under normal trapping conditions that cannot be eliminated by established methods using external DC magnetic fields. In our system, we gain control over the differential light shift by tuning the ellipticity of the polarization of the trapping light. In particular, by tuning to a magic ellipticity, we achieve up to three orders of magnitude decrease in the differential light shift between two specific rotational levels, and improve the rotational coherence time by two orders of magnitude. Along with dipolar interactions between individual molecules, this sets the stage for many opportunities in quantum computing and quantum simulation in our platform.