Abstract

Optical vortices, having an orbital angular momentum due to a helical wavefront, have been intensely employed in various fields, including optical trapping, optical tweezers and spanners for microstructures. Recently, we demonstrated the formation of twisted (chiral) metal nanoneedles by the deposition of optical vortex pulses, in which the orbital angular momentum of the optical vortex is transferred to the melted metal through a laser ablation process. The twisted direction (chirality) of the metal nanoneedle can be controlled merely by the sign of the orbital angular momentum (wavefront helicity) of the optical vortex [1,2].

© 2013 IEEE