Accurate analysis of planar optical waveguide devices using higher-order FDTD scheme

Area of Science:

• Optics and Photonics
• Computational Electromagnetics
• Numerical Analysis

Background:

• Accurate time-domain analysis of planar optical waveguide devices is crucial for designing advanced photonic integrated circuits.
• Conventional finite-difference time-domain (FDTD) methods can be computationally intensive and may suffer from numerical dispersion.
• Developing efficient and accurate numerical techniques is essential for simulating complex optical phenomena.

Purpose of the Study:

• To propose and validate a higher-order finite-difference time-domain (HO-FDTD) numerical method for analyzing planar optical waveguide devices.
• To implement and assess the anisotropic perfectly matched layer (APML) absorbing boundary condition within the HO-FDTD scheme.
• To investigate the numerical dispersion characteristics of the proposed HO-FDTD method.

Main Methods:

• Development of a higher-order finite-difference time-domain (HO-FDTD) numerical scheme.
• Implementation of the anisotropic perfectly matched layer (APML) absorbing boundary condition.
• Numerical simulations of a parallel-slab directional coupler.
• Comparison of simulation results with analytical solutions.

Main Results:

• The HO-FDTD scheme demonstrates high accuracy, with simulation results closely matching analytical solutions for the parallel-slab directional coupler.
• The implemented APML boundary condition effectively absorbs outgoing waves, minimizing reflections.
• Numerical dispersion of the HO-FDTD scheme is analyzed and found to be manageable.

Conclusions:

• The proposed HO-FDTD method offers a computationally efficient alternative to conventional FDTD for optical waveguide analysis.
• This method achieves high accuracy without significant increases in computational cost.
• The HO-FDTD scheme is well-suited for the precise analysis of complex planar optical waveguide devices.