Presentation Information
[10p-E201-5]Rotational Optical Torque of a Sub-shell Structure Induced by Optical-Vortex-Excited LPR (III)
〇Daisuke Tanaka1, Yuto Fujita1, Kenta Oishi1, Fu Koharu1 (1.NIT, Oita College)
Keywords:
optical torque,optical vortex,discrete dipole approximation
Optically driven plasmonic nanomotors are promising for local flow control and light-driven nano/micromechanical systems because optical torque can be applied to nanostructures without contact. In this study, optical torque induced in an asymmetric plasmonic sub-shell particle by optical-vortex-excited localized plasmon resonance was numerically investigated. An optical vortex beam with a topological charge of l = +1 was used, and the torque components around the x-, y-, and z-axes were calculated using the discrete dipole approximation. Finite torque was generated around all three axes, and the torque distributions strongly depended on particle orientation and incident wavelength. These results indicate that the rotation axis and torque direction can be controlled by optical and geometrical parameters.