The coupling of individual atoms to a high-finesse optical cavity is
precisely controlled and adjusted using a standing-wave dipole-force trap, a
challenge for strong atom-cavity coupling. Ultracold Rubidium atoms are first
loaded into potential minima of the dipole trap in the center of the cavity.
Then we use the trap as a conveyor belt that we set into motion perpendicular
to the cavity axis. This allows us to repetitively move atoms out of and back
into the cavity mode with a repositioning precision of 135 nm. This makes
possible to either selectively address one atom of a string of atoms by the
cavity, or to simultaneously couple two precisely separated atoms to a higher
mode of the cavity.Comment: 4 pages 5 figure