Abstract

Optical vortex tweezers, providing orbital angular momentum to trapped particles, have been successfully demonstrated to sort and deliver micro-particles on a mesoscopic-scale [1]. They used mostly a single vortex, in which a single phase singularity is involved in a wavefront. A multiple-vortex with several phase singularities in a wavefront is potentially capable of controlling several independent optical traps, each with individually specified characteristics, by using a single laser. In this paper, we demonstrate the transport of nano-particles to a specified direction in a mesoscopic field by utilizing three independent vortices with individually specified rotational speed and direction, computer-generated from a single laser beam, for the first time. We call this system a holographic multiple-vortex tweezer.

© 2009 IEEE