Adiabatic perturbation theory for mode analysis in optical waveguides with large index variations without eigen value...

Area of Science:

• Photonics and Optical Engineering
• Computational Electromagnetics

Background:

• Eigen mode and eigen value evaluation is critical but time-consuming in optical waveguide design.
• The conventional perturbation method offers efficiency for small index variations but is limited for inverse design problems with large index changes.

Purpose of the Study:

• To develop a novel adiabatic perturbation theory for optical waveguide design.
• To overcome the limitations of traditional perturbation methods in handling large index variations for inverse design.

Main Methods:

• Proposed an adiabatic perturbation theory that evaluates optical waveguide eigen modes and propagation constants incrementally.
• Gradually introduced index variations in small steps to approximate significant structural changes.

Main Results:

• The adiabatic perturbation theory successfully enabled the application of perturbation methods to optical waveguide inverse design problems with large index variations.
• Efficient computation of modes and propagation constants was achieved without resorting to time-consuming eigenvalue decomposition for large index changes.

Conclusions:

• The proposed adiabatic perturbation theory significantly expands the applicability of perturbation methods in optical waveguide inverse design.
• This approach provides an efficient and accurate alternative for analyzing optical waveguides with substantial refractive index modifications.