"It was fascinating to observe the evolution of the vector-vortex beam during propagation"
This talk addresses the up-conversion of vortex and vector-vortex beams from the infrared into the extreme ultraviolet. The control over spin and orbital angular momentum in high harmonic generation (HHG) enables structuring short-wavelength beams in their polarization and phase . We can imprint high topological charges in twisted wavefronts through HHG, reaching values as high as 100 in a recent Hartmann wavefront characterization . By integrating both a spatially-varying phase and polarization in vector-vortex beams, we reveal novel propagation dynamics in HHG and we build-up attosecond light springs with multiple polarization states that can be oriented in radial or azimuthal configurations.
References  A. de las Heras, A. K. Pandey, J. San Román, J. Serrano, E. Baynard, G. Dovillaire, M. Pittman, C. Durfee, L. Plaja, S. Kazamias, O. Guilbaud, and C. Hernández-García, "Extreme-ultraviolet vector-vortex beams from high harmonic generation," Optica, DOI 10.1364/OPTICA.442304 (2021)  A. K. Pandey, A. de las Heras, T. Larrieu, J. San Román, J. Serrano, L. Plaja, E. Baynard, G. Dovillaire, M. Pittman, S. Kazamias, C. Hernández-García, and O. Guilbaud, "Characterization of extreme-ultraviolet vortex beams with very high topological charge" (submitted to ACS Photonics).