Full vectorial analysis of a nonlinear slab waveguide based on the nonlinear hybrid vector finite-element method

Area of Science:

• Nonlinear optics
• Computational electromagnetics
• Waveguide theory

Background:

• Nonlinear waveguides are crucial for advanced optical devices.
• Accurate simulation of optical beam propagation is essential for understanding waveguide behavior.
• Existing methods may have limitations in handling complex nonlinear phenomena in 3D.

Purpose of the Study:

• To introduce a new nonlinear hybrid vector finite-element method (FE-FD) for 3D optical beam propagation.
• To validate the proposed method using a specific planar nonlinear waveguide model.
• To investigate the excitation and emission characteristics of nonlinear slab waveguides.

Main Methods:

• Developed a hybrid method combining edge-element (cross-section) and finite-difference (propagation) techniques.
• Applied the method to simulate a planar nonlinear waveguide with Kerr-type nonlinearity.
• Numerically studied the end-fire excitation of TE(0) and TM(0) modes.

Main Results:

• The proposed FE-FD method effectively simulates 3D optical beam propagation in nonlinear waveguides.
• Numerical simulations of a planar nonlinear waveguide demonstrated predicted behaviors.
• External excitation led to sequential threshold behavior and multisoliton emission.

Conclusions:

• The new nonlinear hybrid vector finite-element method is a powerful tool for studying optical beam propagation.
• Nonlinear slab waveguides exhibit complex emission dynamics, including multisoliton formation.
• The findings contribute to the design and understanding of nonlinear optical devices.