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Updated: Jul 24, 2025
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Automation of Mode Locking in a Nonlinear Polarization Rotation Fiber Laser through Output Polarization Measurements
Published on: February 28, 2016
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Hall Effect at the Focus of an Optical Vortex with Linear Polarization
Victor V Kotlyar1,2, Alexey A Kovalev1,2, Elena S Kozlova1,2
1Laser Measurements Laboratory, Image Processing Systems Institute of the RAS-Branch of FSRC "Crystallography & Photonics" of the RAS, 151 Molodogvardeyskaya St., 443001 Samara, Russia.
Micromachines
|July 8, 2023
Summary
Optical vortices exhibit spin and orbital Hall effects, separating spin and energy flow directions. Angular momentum components are independent, not simply additive, during propagation and focusing.
Area of Science:
- Optics and Photonics
- Quantum Mechanics
Background:
- Optical vortices carry orbital angular momentum (OAM).
- Spin angular momentum (SAM) and OAM influence light-matter interactions.
- Understanding their behavior during focusing is crucial for optical applications.
Purpose of the Study:
- To investigate the behavior of spin and orbital angular momentum components of optical vortices during tight focusing.
- To analyze the conservation laws and emergent phenomena like Hall effects.
Main Methods:
- Theoretical analysis of optical vortex focusing with linear polarization.
- Examination of longitudinal components of SAM and OAM.
- Analysis of energy flux and angular momentum density distributions.
Main Results:
- Longitudinal SAM and OAM are conserved separately during propagation.
- Conservation leads to observable spin and orbital Hall effects (spatial separation of spin states and rotation directions).
- Angular momentum components (SAM, OAM) are independent and not directly additive in the total angular momentum expression.
Conclusions:
- The study elucidates the distinct behaviors of SAM and OAM during optical vortex focusing.
- Spin and orbital Hall effects are direct consequences of conserved SAM and OAM.
- The findings clarify the nature of angular momentum in focused optical fields.
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