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Updated: Jul 22, 2025
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Symmetry-breaking enabled topological phase transitions in spin-orbit optics.
Optics Express
|July 21, 2023
Summary
Topological phase transitions (TPT) in light unify spin-orbit interactions. Focusing Gaussian beams shows TPT evolving from vortex generation to the photonic spin-Hall effect due to symmetry breaking.
Area of Science:
- Optics and Photonics
- Quantum Optics
- Topological Photonics
Background:
- Topological phase transitions (TPT) describe evolutions between spin-orbit interactions.
- TPT has been observed in beam scattering and crystal propagation.
- Spin-orbit interactions in optics include spin-dependent vortex generation and the photonic spin-Hall effect.
Purpose of the Study:
- To investigate TPT in focused Gaussian beams with off-axis and partial masking.
- To unify different spin-orbit interactions within a TPT framework.
- To explore the mechanism of symmetry-breaking induced TPT.
Main Methods:
- Full-wave theoretical analysis.
- Investigation of focused off-axis and partially masked circular-polarization Gaussian beams.
- Vortex mode decomposition for examining symmetry-breaking induced TPT.
Main Results:
- A topological phase transition (TPT) occurs in the focused optical field as off-axis distance or masked area increases.
- The TPT evolves from spin-dependent vortex generation to the photonic spin-Hall effect.
- Cylindrical symmetry-breaking is identified as the intrinsic mechanism driving this TPT.
Conclusions:
- The study unifies spin-dependent vortex generation and photonic spin-Hall effect under the TPT perspective.
- Symmetry-breaking induced TPT in focused optical fields is demonstrated.
- Findings offer insights into spin-orbit interactions and unify TPT phenomena in photonics.
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