Phys.org  October 3, 2022 Researchers in Israel have shown that by using 3D-direct laser writing, high-quality optical devices could be fabricated directly on top of the fiber’s facet by the two-photon absorption process. They demonstrated how a high-order Bessel beam carrying orbital angular momentum could be generated by using this lithography process. The beam is shaped using an integrated micro-optical system that consists of a twisted axicon and parabolic lens in an adapted fiber configuration. They provided the analysis and measurements of the generated beam, along with simulated predictions. They found that the size of the central ring remained nearly […]