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Updated: Oct 17, 2025
12:34
Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence
Published on: June 24, 2016
10.2K
Weak turbulence effects on different beams carrying orbital angular momentum
Summary
Bessel-Gaussian beams retain more orbital angular momentum (OAM) information than Laguerre-Gaussian beams when propagated through atmospheric turbulence. LG beams exhibit lower scintillation across OAM modes.
Area of Science:
- Optical physics
- Free-space optical communications
- Beam propagation
Background:
- Beams carrying orbital angular momentum (OAM) are crucial for applications like free-space optical communications (FSOC), directed energy, and remote sensing (RS).
- Measuring beam wavefront is essential for information recovery in FSOC and RS.
- Understanding beam behavior in atmospheric turbulence is key for reliable optical systems.
Purpose of the Study:
- To computationally investigate and compare the propagation characteristics of Laguerre-Gaussian (LG), Bessel-Gaussian (BG), and Bessel beams through atmospheric turbulence.
- To quantify the impact of turbulence on OAM information retention and beam properties.
Main Methods:
- Simulated atmospheric turbulence using multiple phase screens within a split-step framework.
- Analyzed beam propagation using metrics: spatial coherence radius, OAM spectrum, on-axis intensity, spot size, divergence, and on-axis scintillation.
- Limited simulations to the weak scintillation regime, allowing for Rytov approximation.
Main Results:
- Bessel-Gaussian (BG) beams and multiplexed BG beams demonstrated superior retention of OAM information compared to LG and Bessel beams.
- Laguerre-Gaussian (LG) beam on-axis intensity and scintillation were independent of the OAM mode.
- LG beams showed lower scintillation than BG, Bessel, and Gaussian beams across various OAM modes.
Conclusions:
- BG beams offer advantages in maintaining OAM information integrity in turbulent environments.
- LG beams present a lower scintillation profile, beneficial for applications sensitive to intensity fluctuations.
- Beam divergence plays a role in understanding the observed propagation behaviors.
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