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arXiv · 2207.05074

Topological Transformation and Free-Space Transport of Photonic Hopfions

Yijie Shen·Bingshi Yu·Haijun Wu·Chunyu Li·Zhihan Zhu·Anatoly V. Zayats
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Abstract

Structured light fields embody strong spatial variations of polarisation, phase and amplitude. Understanding, characterization and exploitation of such fields can be achieved through their topological properties. Three-dimensional (3D) topological solitons, such as hopfions, are 3D localized continuous field configurations with nontrivial particle-like structures, that exhibit a host of important topologically protected properties. Here, we propose and demonstrate photonic counterparts of hopfions with exact characteristics of Hopf fibration, Hopf index, and Hopf mapping from real-space vector beams to homotopic hyperspheres representing polarisation states. We experimentally generate photonic hopfions with on-demand high-order Hopf indices and independently controlled topological textures, including N\'eel-, Bloch-, and anti-skyrmionic types. We also demonstrate a robust free-space transport of photonic hopfions, thus, showing potential of hopfions for developing optical topological informatics and communications.

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Yijie Shen, Bingshi Yu, Haijun Wu, Chunyu Li, Zhihan Zhu, Anatoly V. Zayats. 2022-07-11. Topological Transformation and Free-Space Transport of Photonic Hopfions. https://doi.org/10.1117/1.ap.5.1.015001

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