Accurate and efficient leap-frog beam propagation method for modeling micro and nanophotonic structures

Area of Science:

• Photonics
• Computational Electromagnetics
• Optical Engineering

Background:

• The Beam Propagation Method (BPM) is crucial for simulating light propagation in optical systems.
• Conventional BPM methods can be computationally intensive, limiting simulation speed.
• Efficient numerical techniques are needed for accurate modeling of complex photonic structures.

Purpose of the Study:

• To introduce a novel and efficient approach for solving the BPM governing equation.
• To enhance computational speed in optical system modeling.
• To validate the proposed method through simulations and experimental verification.

Main Methods:

• Reformulating the BPM equation to solve only real system matrices at each step.
• Utilizing a leap-frog (LF) technique to couple real and imaginary field components iteratively.
• Simulating various photonic systems, including directional couplers and multimode interferometers.

Main Results:

• The proposed LF-BPM method achieves at least 30% higher processing speed compared to conventional BPM.
• Simulations of directional couplers and multimode interferometers were successfully performed.
• Experimental verification confirmed the accuracy of the LF-BPM results for fabricated micro-photonic structures.
• Stability analysis demonstrated the robustness of the LF-BPM scheme.

Conclusions:

• The LF-BPM approach offers a significant speed improvement for optical system modeling.
• The method provides accurate and experimentally validated results.
• LF-BPM is a promising technique for efficient and reliable modeling of optical structures.