Multiplexed vortex beam-based optical tweezers

TL;DR

This paper presents a novel multiplexed vortex beam optical tweezer system that generates multiple concentric vortex beams with independent topological charges, enabling complex particle manipulation and angular momentum transfer.

Contribution

It introduces a new phase mask design for multiplexed vortices with independent topological charges in optical tweezers, demonstrating experimental control over particle dynamics.

Findings

Successful generation of multiple concentric vortex beams

Transfer of angular momentum to microparticles

Control of particle orbiting dynamics

Abstract

The design and implementation of a multiplexed spiral phase mask in an experimental optical tweezer setup are presented. This diffractive optical element allows the generation of multiple concentric vortex beams with independent topological charges. The generalization of the phase mask for multiple concentric vortices is also shown. The design for a phase mask of two multiplexed vortices with different topological charges is developed. We experimentally show the transfer of angular momentum to the optically trapped microparticles by enabling orbiting dynamics around the optical axis independently within each vortex. The angular velocity of the confined particles versus the optical power in the focal region is also discussed for different combinations of topological charges.