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Published on: August 30, 2013
Application of the three-dimensional aperiodic Fourier modal method using arc elements in curvilinear coordinates
Davide Bucci1, Bruno Martin, Alain Morand
1IMEP-LAHC, Grenoble INP-Minatec: 3, Grenoble, France. davide.bucci@grenoble-inp.fr
Summary
This study presents a vectorial generalization of the aperiodic Fourier modal method (AFMM) in cylindrical coordinates for predicting waveguide bending losses. Results align with finite-difference time-domain (FDTD) simulations, validating the AFMM approach for complex waveguide structures.
Area of Science:
- Computational electromagnetics
- Photonics and optical engineering
- Waveguide theory
Background:
- Accurate prediction of bending losses in optical waveguides is crucial for integrated photonic device design.
- Existing methods may face limitations with arbitrary refractive index profiles and cylindrical geometries.
Purpose of the Study:
- To develop and validate a full vectorial aperiodic Fourier modal method (AFMM) in cylindrical coordinates.
- To predict key characteristics, specifically bending losses, of waveguides with arbitrary transverse refractive index distributions.
Main Methods:
- Full vectorial generalization of the aperiodic Fourier modal method (AFMM) in cylindrical coordinates.
- Numerical simulations using the finite-difference time-domain (FDTD) method for comparison.
- Analysis of an S-bend silicon waveguide structure in silica at a wavelength of 1550 nm.
Main Results:
- The cylindrical coordinates AFMM successfully predicts waveguide characteristics.
- AFMM results show good agreement with FDTD simulations for bending losses.
- Differences between AFMM and FDTD were comparable to parameter variations within FDTD.
Conclusions:
- The developed cylindrical AFMM is a viable and accurate method for analyzing bending losses in complex waveguide structures.
- This method offers a powerful tool for the design and optimization of photonic integrated circuits.
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