Fast optical transport of ultracold molecules over long distance

Optically trapped laser cooled polar molecules are an attractive platform for quantum information and quantum simulation. Long molecular lifetimes and large numerical aperture optical access is needed, but can be difficult to achieve in a typical MOT apparatus with a cryogenic buffer gas beam source. Long distance transport places molecules into a chamber separate from the MOT, easing the difficulty of fulfilling these requirements. We present a fast transport method for ultracold molecules based on an electronically focus-tunable lens. The high transport speed is achieved by employing 1D red-detuned optical lattice generated by interference of a focus-tunable laser beam and a focus-fixed laser beam. Transport of ultracold CaF molecules over 45 cm distance is realized in less than 50 ms with no significant heating. Fluctuation in the final position of the transported molecular cloud is small, allowing stable loading into an optical tweezer array.