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Updated: Apr 23, 2026
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Scanning SQUID Study of Vortex Manipulation by Local Contact
Published on: February 1, 2017
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Light-matter interaction induces a single positive vortex with swirling arms
R Barboza1, U Bortolozzo2, M G Clerc3
1Departamento de Física, FCFM, Universidad de Chile, Casilla 487-3, Santiago, Chile INLN, Université de Nice-Sophia Antipolis, CNRS, 1361 Route des Lucioles, 06560 Valbonne, France.
Summary
Localized light creates stable optical vortexes in homeotropic nematic liquid crystals. An amplitude equation explains the vortex origin and swirling arm dynamics near the Fréedericksz transition.
Area of Science:
- Physics
- Materials Science
- Optics
Background:
- Nematic liquid crystals (NLCs) are anisotropic fluids with unique optical properties.
- Photosensitive materials offer dynamic control over NLC behavior.
- Homeotropic alignment and negative dielectric anisotropy are crucial for specific electro-optic effects.
Purpose of the Study:
- To investigate the formation and characteristics of stable vortexes in homeotropic NLC cells with photosensitive walls.
- To elucidate the underlying physics of light-induced vortex generation.
- To analyze the interplay between illumination patterns and elastic forces.
Main Methods:
- Utilizing homeotropic nematic liquid crystal cells with photosensitive walls.
- Applying local illumination to induce changes in the NLC.
- Deriving an amplitude equation near the Fréedericksz transition.
Main Results:
- Stable vortexes with swirling arms were observed and trapped at illuminated areas.
- The derived amplitude equation successfully describes the origin of the induced vortex.
- The competition between the illumination profile and elastic anisotropy dictates vortex arm swirling.
Conclusions:
- Local illumination of homeotropic NLCs with photosensitive walls can induce stable optical vortexes.
- Amplitude equations provide a theoretical framework for understanding light-driven NLC phenomena.
- This work offers insights into controlling light-matter interactions in anisotropic fluids.
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