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Electromagnetic Schell-model sources generating far fields with stable and flexible concentric rings profiles.
Optics Express
|November 3, 2017
Summary
Researchers introduced new electromagnetic sources that create beams with tunable, concentric ring patterns. These beams maintain their structure in free space and offer control over polarization and intensity distribution.
Area of Science:
- Electromagnetism and Optics
- Mathematical Physics
Background:
- Gaussian Schell-model (GSM) sources are widely used in optical beam propagation studies.
- Understanding the statistical properties of light beams is crucial for various applications.
Purpose of the Study:
- To introduce a new class of electromagnetic sources with a multi-cosine GSM correlation function.
- To establish realizability and beam conditions for these novel sources.
- To analyze the propagation characteristics and statistical properties of the generated beams.
Main Methods:
- Derivation of analytical formulas for the cross-spectral density matrix.
- Propagation analysis in free space.
- Numerical simulations to examine statistical properties.
Main Results:
- Introduction of multi-cosine GSM sources.
- Established realizability and beam conditions.
- Demonstrated invariant far-field concentric rings-like intensity patterns.
- Observed uniform polarization state across rings.
- Found generally different degree of polarization values on different rings.
- Showcased tunability of ring number and beam characteristics via source parameters.
Conclusions:
- The proposed multi-cosine GSM sources offer a flexible platform for generating beams with controllable ring structures.
- These beams exhibit unique polarization and intensity distributions.
- The ability to tune beam characteristics provides potential for advanced optical applications.
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