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Updated: Apr 3, 2026
12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
22.6K
Light trajectory in Bessel-Gauss vortex beams
Summary
Bessel-Gauss vortex beams transition from expanding rings to a diffraction-free state. Using hollow input beams can eliminate this transition regime for better beam control.
Area of Science:
- Optics and Photonics
- Laser Physics
Background:
- Bessel-Gauss vortex beams exhibit unique propagation characteristics.
- Understanding their early-stage dynamics is crucial for applications.
Purpose of the Study:
- To investigate the transition regime in Bessel-Gauss vortex beam propagation.
- To characterize the beam structure and identify methods to control its dynamics.
Main Methods:
- Utilized the eikonal equation to model beam structure.
- Employed analytical, numerical, and experimental approaches.
- Investigated the effect of hollow input beams.
Main Results:
- Observed a progressive lateral expansion of the main intensity ring during the transition regime.
- Characterized the beam structure using hyperboloids with variable waists, forming a tapered tubular caustic.
- Demonstrated excellent agreement between analytical, numerical, and experimental results.
- Showed that hollow input beams eliminate the transition regime.
Conclusions:
- The early propagation of Bessel-Gauss vortex beams involves a distinct transition regime.
- The eikonal equation effectively describes the beam's hyperbolic structure.
- Hollow input beams offer a method to bypass the transition, leading to a more direct diffraction-free propagation.
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