Structured Light and Its Applications

Chapter 8 Optical Vortex Trapping and the Dynamics of Particle Rotation

Timo A. Nieminen, Simon Parkin, Theodor Asavei, Vincent L.Y. Loke, Norman R. Heckenberg, Halina Rubinsztein-Dunlop

University of Queensland, Australia

8.1 INTRODUCTION

Since the pioneering work by He and colleagues [34,35], the transport of optical angular momentum by optical vortex beams has been applied to the rotation of microscopic particles in optical traps. Even earlier, optical vortex traps had been proposed as a method to reduce the scattering forces that oppose optical trapping; in the ray optics picture, only high-angle rays contribute to the gradient force, and the use of a hollow beam eliminates the low-angle rays that would still contribute to the scattering ...