Multifunctional optical meta-tweezers with polarization-based modulation

Abstract

The use of optical trapping has become increasingly prevalent in scientific domains such as biology and physics. However, the realization of various trapping effects often requires the switching of equipment components. To address this challenge, we propose a novel approach that combines the dynamic and geometric phases with polarization multiplexing to create a monolayer multifunctional metasurface optical tweezer based on polarization modulation. Our method utilizes different circular polarizations of light to produce a both focused Gaussian field and a focused optical vortex (OV) field. Numerical simulations demonstrate that the focused Gaussian fields can effectively trap high refractive index (RI) particles, while the focused OV fields can be used as an optically controlled spanner to rotate and manipulate particles or trap low RI particles. Additionally, we present an array of polarization modulation metasurface tweezers that have the potential to trap and manipulate particles of varying radii and diverse motion behaviors. Overall, our work highlights the efficacy of polarization-modulation multifunctional metasurface tweezers in combining several trapping tasks into one device. These tweezers have promising potential for integration into future lab-on-chip technologies.