Accelerating, guiding, and sub-wavelength trapping of neutral atoms with tailored optical vortices

Abstract

Single neutral atom mechanics is controllable by focused, high-intensity optical vortices. The intensity-dependent, laser-driven motion of the atom's active electrons subsumes to a net transfer of the orbital angular momentum of the light to the neutral atom. The ponderomotive force on these electrons translates so into an unbounded or a bounded radial drift of the atom depending on its initial kinetic energy, as set by the temperature. Appropriate combination of laser beams results in sub-wavelength, dynamical radial traps for tweezing atoms controllably, an effect that can be exploited for atom guiding, structuring, and lithographic applications.