Open access
Date
2023-05-08Type
- Journal Article
Abstract
Light beams with Orbital Angular Momentum (OAM) are explored in applications from microscopy to quantum communication, while the Talbot effect revives in applications from atomic systems to x-ray phase contrast interferometry. We evidence the topological charge of an OAM carrying THz beam in the near-field of a binary amplitude fork-grating by means of the Talbot effect, which we show to persist over several fundamental Talbot lengths. We measure and analyze the evolution of the diffracted beam behind the fork grating in Fourier domain to recover the typical donut-shaped power distribution, and we compare experimental data to simulations. We isolate the inherent phase vortex using the Fourier phase retrieval method. To complement the analysis, we assess the OAM diffraction orders of a fork grating in the far-field using a cylindrical lens. Show more
Permanent link
https://doi.org/10.3929/ethz-b-000614375Publication status
publishedExternal links
Journal / series
Optics ExpressVolume
Pages / Article No.
Publisher
OpticaOrganisational unit
02205 - FIRST-Lab / FIRST Center for Micro- and Nanoscience
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