Observation of radiation pressure trapping of particles by alternating light beams.

The new principle of radiation pressure trapping of neutral dielectric particles using alternating light beams was demonstrated in an optical levitation experiment. Stable trapping of micron- sized spheres was observed due to alternating scattering force fields under conditions where stable c trapping was not possible. Application of this principle to neutral atom trapping as a means of circumventing the Optical Earnshaw Theorem is suggested. A new stable cw optical trap for spheres was also discovered.