# Experimental generation of optimally chiral azimuthally-radially polarized beams

## TL;DR

Researchers created a new type of light beam with optimal chirality, which could be useful for sensing and manipulating chiral particles at the nanoscale.

## Contribution

The paper introduces and experimentally generates a novel class of azimuthally-radially polarized beams with optimal chirality.

## Key findings

- A paraxial azimuthally-radially polarized beam was experimentally generated with maximum chirality density.
- Chirality density can be finely adjusted by manipulating a single beam parameter.
- Optimally chiral beams have potential for optical enantioseparation and enantiomer detection at the nanoscale.

## Abstract

We implement a paraxial azimuthally-radially polarized beam (ARPB), a novel class of structured light beams that can be optimal chiral (OC), leading to maximum chirality density at a given energy density. By using vectorial light shaping techniques, we successfully generated a paraxial ARPB with precise control over its features, validating theoretical predictions. Our findings demonstrate the ability to finely adjust the chirality density of the ARPB across its entire range by manipulating a single beam parameter. Although our experimental investigations are primarily focused on the transverse plane, we show that fields whose transverse components satisfy the optimal chirality condition are optimally chiral in all directions, and our results highlight the promising potential of OC structured light for applications in the sensing and manipulation of chiral particles. We show that helicity density is more general than the concept of handedness. This work represents a significant advancement toward practical optical enantioseparation and enantiomer detection at the nanoscale.