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Updated: May 11, 2025
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
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Inherent Spin-Orbit Locking in Topological Lasing via Bound State in the Continuum
Jiajun Wang1, Xinhao Wang1, Zhaochen Wu1
1Fudan University, State Key Laboratory of Surface Physics, Key Laboratory of Micro- and Nano-Photonic Structures (Ministry of Education) and Department of Physics, Shanghai 200433, China.
Physical Review Letters
|April 18, 2025
Summary
Bound states in the continuum (BICs) exhibit topological polarization vortices. This study demonstrates inherent spin-orbit locking in topological BIC lasing, revealing novel photonic phenomena.
Area of Science:
- Optics
- Condensed Matter Physics
- Topological Photonics
Background:
- Bound states in the continuum (BICs) are optical topological singularities with ultrahigh quality factors.
- BICs enable lasing and Bose-Einstein condensation, and their topological properties reveal spin-orbit photonic effects.
Purpose of the Study:
- To demonstrate inherent spin-orbit locking in topological BIC lasing.
- To explore new spin-orbit locking phenomena in photonic crystals.
Main Methods:
- Utilizing C4v and C6v photonic crystal slabs.
- Achieving BIC lasing with +1 and -2 topological charges.
- Observing spin-orbit locking via momentum-space self-interference patterns.
Main Results:
- Distinct spin-orbit locking combinations were achieved in BIC lasing.
- Spin-orbit locking phenomena were directly observed in momentum space.
- Real-space spin separations were revealed as a counterpart to momentum-space effects.
Conclusions:
- New spin-orbit locking phenomena in BIC lasing were discovered.
- Results show potential for advancements in topological photonic sources.
- Demonstrated inherent spin-orbit locking in topological BIC lasing.
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