Optically induced propulsion of microparticles in an evanescent field of a multimode channeled waveguide

We report experimental results in which Mie particles were optically propelled in an evanescent field generated in a multimode channeled waveguide. Polystyrene latex spheres 4 micrometers in diameter were trapped laterally in the high intensity region of an evanescent field and were driven along the waveguide channel in an evanescent field of either fundamental or higher guided modes. In addition, when the multiple guided modes are excited simultaneously, the distribution of the meandering light's intensity is generated in the waveguide due to the coupling of the modes. The small particles are laterally trapped even in this meandering beat pattern and driven in a meandering fashion along the waveguide channels.