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Updated: May 8, 2026
12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
Cosine-Gaussian Schell-model sources.
Zhangrong Mei1, Olga Korotkova
1Department of Physics, Huzhou Teachers College, Huzhou, China. meizhangrong@yahoo.com
Optics Letters
|August 14, 2013
Summary
We introduce novel partially coherent sources with a cosine-Gaussian spectral degree of coherence. These sources generate beams that evolve to exhibit a Gaussian coherence profile and dark-hollow spectral density at far distances.
Area of Science:
- Optics and Photonics
- Classical Optics
- Coherence Theory
Background:
- Partially coherent sources are crucial in various optical applications.
- Schell-type sources offer a tractable model for coherence properties.
- Characterizing spectral coherence is essential for understanding beam propagation.
Purpose of the Study:
- To introduce and validate a new class of partially coherent Schell-type sources.
- To derive the cross-spectral density of beams from these novel sources.
- To analyze the propagation dynamics of spectral density and coherence.
Main Methods:
- Theoretical derivation of the cross-spectral density function.
- Analysis of spectral density and spectral degree of coherence evolution.
- Mathematical modeling of beam propagation in free space.
Main Results:
- Confirmation of the physical genuineness of the proposed partially coherent sources.
- Derivation of the cross-spectral density function for the novel source.
- Demonstration of the spectral degree of coherence evolving to a Gaussian shape.
- Observation of the spectral density developing a dark-hollow profile at far distances.
Conclusions:
- The novel cosine-Gaussian Schell-type sources are physically valid.
- The derived cross-spectral density accurately describes beam propagation.
- Far-field beam characteristics are predictable and controllable through source parameters.
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