Imaginary Poynting momentum driven particle rotation by cylindrically polarized Gaussian beams

TL;DR

This paper demonstrates that imaginary Poynting momentum in cylindrically polarized Gaussian beams can induce controllable rotation of gold microparticles, offering a new method for particle manipulation without spin or orbital angular momentum.

Contribution

The study introduces the use of imaginary Poynting momentum for particle rotation, expanding the understanding of light-matter interactions in optical manipulation.

Findings

Gold particles rotate azimuthally under IPM influence

Rotation controllable via polarization tuning

IPM transfer is competitive with spin angular momentum

Abstract

Imaginary Poynting momentum (IPM) provides a new degree of freedom for particle manipulation. However, the application of IPM in experiments has been largely unexplored. Here, we demonstrate the IPM driven particle rotation by cylindrically polarized Gaussian beams with no spin or orbital angular momentum. Theoretical analysis and experimental measurements demonstrate that gold microparticles will be rotated in the azimuthal direction while confined in the radial direction. We achieved controllable rotation of the particle by tuning the cylindrical polarization state. Interestingly, the transfer of IPM to a gold particle is demonstrated to be competitive with that of spin angular momentum. These findings hold promising in light-matter interactions and particle manipulations.