Nonlinearity-induced optical torque

Abstract

Optically-induced mechanical torque leading to the rotation of small objects requires the presence of absorption or breaking cylindrical symmetry of a scatterer. A spherical non-absorbing particle cannot rotate due to the conservation of the angular momentum of light upon scattering. Here, we suggest a novel physical mechanism for the angular momentum transfer to non-absorbing particles via nonlinear light scattering. The breaking of symmetry occurs at the microscopic level manifested in nonlinear negative optical torque due to the excitation of resonant states at the harmonic frequency with higher projection of angular momentum. The proposed physical mechanism can be verified with resonant dielectric nanostructures, and we suggest some specific realizations.

7 pages, 4 figures

References in corpus (9)

• Optical alignment and spinning of laser-trapped microscopic particles
• High-Q supercavity modes in subwavelength dielectric resonators
• Optical Momentum, Spin, and Angular Momentum in Dispersive Media
• Optical manipulation with metamaterial structures
• Resonant state expansion applied to three-dimensional open optical systems
• Multipolar second-harmonic generation by Mie-resonant dielectric nanoparticles
• Negative optical torque on a microsphere in optical tweezers
• Directional emission of down-converted photons from a dielectric nano-resonator
• When does nonlinear circular dichroism appear in achiral dielectric nanoparticles?

Cited by in corpus (5)

• Fast simulation of light scattering and harmonic generation in axially symmetric structures in COMSOL
• Switchable optical trapping of Mie-resonant phase-change nanoparticles
• Radiation forces and torques in optics and acoustics
• Optical Supertorque Induced by Mie-Resonant Modes
• Achiral nanostructures: perturbative harmonic generation and dichroism under vortex and vector beams illumination