Abstract

Conventional optical manipulation uses the gradient optical forces to trap an object in the focus of a 3D laser beam. Within a perspective of miniaturization, the implementation of optical tweezers at a surface opens a huge potential towards the elaboration of future lab-on-a-chip devices entirely operated with light. The transition from 3D to 2D is rendered possible by exploiting evanescent fields bound at interfaces. Particularly, Surface Plasmons (SP) at metal/dielectric interfaces are expected to be excellent candidates to relax the requirements on incident power and to achieve sub-wavelength trapping volumes. Our current work provides a first experimental demonstration of a novel in-plane manipulation method based on the action of SP forces rather than conventional photonic forces, both at homogeneous and patterned metal surfaces.

© 2007 IEEE