Enhancing the capabilities of generating THz vortices by utilizing advanced spiral zone plates based on carbon nanotubes

Opticalelements based on nanomaterials have gained significant attention due to their potential for advancing research in the terahertz (THz) region. These materials offer compactness and unique properties such as flexibility and stretchability, which enable precise control of wave beams. In this work, we demonstrate an innovative approach to controlling the THz wavefront using spiral zone plates (SZPs) made of single-walled carbon nanotubes (SWCNTs). As a demonstration of the concept, we design the SZP using Laguerre-Gauss mode analysis, and subsequently fabricate and experimentally characterize the resulting vortex beams.