Adaptive step-size algorithm for Fourier beam-propagation method with absorbing boundary layer of auto-determined...

Area of Science:

• Computational physics
• Optics and photonics
• Numerical methods

Background:

• The absorbing boundary layer (ABL) is crucial for simulating wave propagation in open regions.
• Traditional ABL methods can suffer from inaccuracies due to improper parameter selection and numerical artifacts.
• The Fourier beam-propagation method (FBPM) is widely used but requires effective boundary conditions.

Purpose of the Study:

• To introduce two novel algorithms designed to enhance the effectiveness of the absorbing boundary layer (ABL) within the Fourier beam-propagation method (FBPM).
• To improve the accuracy and efficiency of optical simulations by addressing limitations in existing ABL techniques.

Main Methods:

• Development of an automated boundary layer width selector that dynamically determines optimal ABL size based on initial beam characteristics.
• Implementation of a beam-shape-adaptive algorithm to adjust propagation step sizes, mitigating aliasing artifacts during simulation.

Main Results:

• The automated width selector provides near-optimal boundary layer dimensions, simplifying setup and improving simulation stability.
• Adaptive step size adjustment effectively reduces aliasing errors, leading to more faithful propagation modeling.
• Combined, these algorithms enhance the overall utility and reliability of the ABL in FBPM simulations.

Conclusions:

• The presented algorithms offer significant improvements for implementing absorbing boundary layers in beam propagation simulations.
• These advancements contribute to more accurate and robust computational modeling in optics and photonics.
• The automated and adaptive nature of the algorithms reduces manual intervention and enhances simulation fidelity.