Experimental measurement of the self-healing of the spatially inhomogeneous states of polarization of radially and azimuthally polarized vector Bessel beams

TL;DR

This study experimentally demonstrates that the complex polarization states of radial and azimuthal vector Bessel beams can self-heal after encountering obstructions, which is promising for applications like optical trapping.

Contribution

First experimental measurement of the self-healing of the polarization states in vector Bessel beams using digital generation and Stokes polarimetry.

Findings

Polarization states of vector Bessel beams self-heal after obstruction.

Self-healing explained via interference of conical rays.

Potential applications in optical trapping.

Abstract

We experimentally measured the self-healing of the spatially inhomogeneous states of polarization of radial and azimuthal polarized vector Bessel beams. Radial and azimuthal polarized vector Bessel beams were generated via a digital version of Durnin's method, using a spatial light modulator in concert with a liquid crystal $q$-plate. As a proof of principle, their intensities and spatially inhomogeneous states of polarization were measured using Stokes polarimetry as they propagated through two disparate obstructions. It was found, similar to their intensities, the spatially inhomogeneous states of polarization of a radial and azimuthal polarized vector Bessel beams self-heal. Similar to scalar Bessel beams, the self-healing of vector Bessel beams can be understood via geometric optics, i.e., the interference of the unobstructed conical rays in the shadow region of the obstruction. The self-healing of vector Bessel beams may have applications in, for example, optical trapping.