AUTHORS:

Nguyen H.T., Kasztelanic R., Pysz D., Le H.V., Stepien R., Omatsu T., Krolikowski W., Buczynski R.

ABSTRACT:

We report theoretical and experimental studies on generation of high-order optical vortex beams using fiber-based nanostructured gradient index converters. The components were made of two types of in-house developed soft glasses with lead, bismuth, gallium compositions to ensure the high refractive contrast of the synthesized glasses. As a result, the vortex components, fabricated using the stack-and-draw method, allow converting Gaussian beam into vortex beams with high-order topological charges in the visible and near-infrared regions. We experimentally verified the formation of optical vortex beams with topological charge up to 5 by using the free-space binary-nanostructured vortex components. In addition, the vortex converter integrated into the standard fiber tip generated optical vortex beams with topological charge up to 4.

Optics & Laser Technology, 2024, vol. 172, art. 110490, doi: 10.1016/j.optlastec.2023.110490