Phys.org January 19, 2023
Achieving hopfions with light waves is very elusive. An international team of researchers (UK, China) proposed and demonstrated photonic counterparts of hopfions with exact characteristics of Hopf vibration, Hopf index, and Hopf mapping from real-space vector beams to homotopic hyperspheres representing polarization states. They experimentally generated photonic hopfions with on-demand high-order Hopf indices and independently controlled topological textures, including Néel-, Bloch-, and antiskyrmionic types. They also demonstrated a robust free-space transport of photonic hopfions, thus showing the potential of hopfions for developing optical topological informatics and communications. According to the researchers their work provides a theoretical background describing the emergence of this family of hopfions and their experimental generation and characterization, revealing a rich structure of topologically protected polarization textures. Their model of optical topological hopfions can be easily extended to other higher-order topological formations in other branches of physics…read more. Open Access TECHNICAL ARTICLE
The parameter-space visualization of a hypersphere… Credit: SPIE 10 January 2023