Oral presentation

Session Information

Location: Science and Cultural Center - FORTH
Day: 2. Thursday 17th
Time: 09:00-09:30
Chairperson: to be announced…

Presentation Details

Presentation Type: Oral presentation
Title: Taming light topology with advanced metaoptics
Abstract: Topological light fields have recently emerged as a powerful platform for robust photonic applications, exploiting topological invariants to encode complex phase and polarization patterns that are intrinsically resilient to perturbations. Among them, optical skyrmions and hopfions extend singular optics beyond isolated defects to multidimensional polarization textures with unique propagation dynamics. However, their practical implementation has so far been hindered by bulky optical setups and the lack of compact, versatile devices for their integrated generation and control. Here, we present a unified metasurface framework for the tailored generation and dynamic manipulation of topological light fields. Based on anisotropic dielectric meta-atoms, the proposed dual-functional metasurfaces independently engineer the two spin channels within a single flat optical element, enabling asymmetric phase/amplitude control and wavefront shaping. This approach provides direct access to a broad family of full-Poincaré beams exhibiting 2D skyrmionic textures as well as 3D optical hopfions. The flexibility of the metasurface design enables advanced propagation dynamics and reconfigurable topological light engineering. For optical skyrmions, precise wavefront engineering combined with polarization control enables the dynamic tuning of the skyrmionic state and topological order during propagation, providing a versatile route to tailor the underlying polarization texture and its associated topology. Extending this concept to 3D topological fields, optical hopfions are generated and continuously reconfigured by simply varying the incident polarization state, while the metasurface simultaneously performs the modal engineering and focusing required for their volumetric synthesis. Experimental demonstrations include high-quality representative hopfionic fields with different Hopf invariants, reconstructed through volumetric Stokes polarimetry. These results establish metasurfaces as a scalable and highly versatile platform for engineering topological light, opening new opportunities for integrated photonic technologies based on topological protection, including optical communications, sensing, information processing, and quantum photonics.

Presenter

Prof Gianluca Ruffato
University of Padova, Department of Physics and Astronomy | Italy

Authors

1. Ruffato, Gianluca | Department of Physics and Astronomy, University of Padova, Italy
2. Vogliardi, Andrea | Department of Physics and Astronomy, University of Padova, Italy
3. Bonaldo, Daniele | {Affiliation3:value}
4. Apolloni, Vittorio | Department of Physics and Astronomy, University of Padova, Italy
5. Dal Zilio, Simone | MetaPhoX Srl, Padova, Italy
6. Romanato, Filippo | Department of Physics and Astronomy, University of Padova, Italy