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Updated: Jul 3, 2026
12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
Transmission optimization and mode crosstalk suppression in optical-system-modulated perfect vortex beams.
Optics Express
|July 2, 2026
Summary
This study optimizes perfect vortex (PV) and focused perfect vortex (FPV) beams using a beam-expanding system. The modulated beams show improved OAM mode reception probability in atmospheric turbulence.
Area of Science:
- Optical physics
- Beam propagation
- Turbulence effects
Background:
- Perfect vortex (PV) and focused perfect vortex (FPV) beams possess unique propagation characteristics.
- Atmospheric turbulence significantly degrades beam quality and orbital angular momentum (OAM) stability.
- Effective beam modulation techniques are crucial for robust free-space optical communication.
Purpose of the Study:
- To investigate transmitter-side beam modulation of PV and FPV beams using a two-lens beam-expanding collimation system.
- To analyze the impact of atmospheric turbulence on modulated PV/FPV beam propagation.
- To optimize system parameters for enhanced OAM mode received probability.
Main Methods:
- Utilized a conventional two-lens beam-expanding collimation system for beam modulation.
- Investigated three transmission scenarios in free space and non-Kolmogorov weak-fluctuation atmospheric turbulence.
- Employed Latin hypercube sampling (LHS)-assisted particle swarm optimization (PSO) combined with pattern search for parameter optimization.
Main Results:
- The system effectively regulates the non-diffractive and focusing regions of PV/FPV beams.
- Modulated PV/FPV beams exhibit improved target OAM mode received probability in turbulence.
- Received probability depends on initial beam parameters, system magnification, FPV focal parameter, and receiver aperture radius.
Conclusions:
- Optimized FPV beams modulated by the beam-expanding collimation system outperform direct FPV propagation in terms of received probability.
- The study provides theoretical guidance for selecting transmitter-side beam and system parameters for free-space optical communication.
- Transmitter-side modulation offers a viable strategy to enhance the performance of vortex beams in turbulent environments.
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