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Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
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Observation of self-induced optical vortex precession
Mohamed El Ketara1, Etienne Brasselet1
1Université Bordeaux, Laboratoire Ondes et Matière d'Aquitaine, UMR 5798, F-33400 Talence, France and CNRS, Laboratoire Ondes et Matière d'Aquitaine, UMR 5798, F-33400 Talence, France.
Physical Review Letters
|August 29, 2014
Summary
Researchers observed optical vortex self-induced precession due to nonlinear light-liquid crystal interactions. This instability breaks axial symmetry, causing orbital motion and demonstrating a novel spin to orbital angular momentum conversion.
Area of Science:
- Nonlinear optics
- Liquid crystal physics
- Photonics
Background:
- Light exhibits spin and orbital angular momentum.
- Nonlinear optical phenomena arise from intense light-matter interactions.
- Liquid crystals are anisotropic media sensitive to light polarization.
Purpose of the Study:
- To investigate the self-induced precession of optical vortices in liquid crystals.
- To explore the spin-orbit interaction instability of light.
- To demonstrate the self-conversion of spin to orbital angular momentum.
Main Methods:
- Experimental observation of optical vortex dynamics.
- Utilizing nonlinear light-liquid crystal interactions.
- Characterizing the spontaneous axial symmetry breaking.
Main Results:
- Observed self-induced precession of an optical vortex.
- Identified an instability in the spin-orbit interaction of light.
- Experimentally demonstrated a nonlinear spin Hall effect of light.
- Showcased self-conversion of spin to extrinsic orbital angular momentum.
Conclusions:
- The nonlinear interaction between light and liquid crystals can induce optical vortex precession.
- This phenomenon reveals a novel mechanism for light's spin-orbit interaction.
- An original demonstration of spin to orbital angular momentum self-conversion is achieved.
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