Interfacing of an optical nanofiber with tunably spaced atoms in an optical lattice

We experimentally demonstrate efficient interfacing of a large number of atoms to an optical nanofiber using an optical lattice with tunable spacing ($0.88-1.5~μ$m) projected onto the nanofiber. The lattice beam and reflections from the nanofiber yield trap potentials that provide tight confinement in all motional degrees of freedom ≈ 220 nm above the nanofiber surface, enabling efficient atom-photon coupling. We achieve trapping of ≈1300 atoms in periodic trap sites with a trap lifetime of ≈15 ms. We also observe the effect of varied lattice periods on the atomic motional frequencies. Our new scheme is adaptable to other nanophotonic cold-atom systems and provides a versatile and scalable platform for studying photon-mediated long-range collective interactions.