Tailored optical potentials for Cs atoms above waveguides with focusing dielectric nano-antenna

Tuning the near-field using all-dielectric nano-antennae offers a promising approach for trapping atoms, which could enable strong single-atom/photon coupling. Here we report the simulation results of an optical trapping concept, in which a silicon nano-antenna produces a trapping potential for atoms in a chip-scale configuration. Using counter-propagating incident fields, bichromatically detuned from the atomic cesium D-lines, we numerically investigate the dependence of the optical potential on the nano-antenna geometry. We tailor the near-field potential landscape by tuning the evanescent field of the waveguide using a toroidal nano-antenna, a configuration that enables trapping of ultracold Cs atoms.