The impact of spurious modes in the modal analysis and bpm schemes for the fem modeling of optical waveguides

Author(s)

Luciano Prado de Oliveira

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Elétrica e de Computação
• Defense date: 2013-02-28

Examining board members

Hugo Enrique Hernández Figueroa; José Patrocinio da Silva; Vitaly Félix Rodríguez Esquerre; Leonardo Lorenzo Bravo Roger; Michel Zamboni Rached

• Advisor: Hugo Enrique Hernández Figueroa

Abstract

This work shows a study of the effects of spurious modes in the modal analysis and in beam propagation schemes based on finite element mixed for modeling bidimensional waveguides structures. The presence of spurious modes in the spectrum of the finite element matrices is investigated and discussed from an alternative formulation for modal analysis of two-dimensional waveguides, where the divergence-free condition is imposed on the vector wave equation. A new beam propagation scheme is proposed by replacing the longitudinal component of the vectorial wave equation with Gauss equation, and analysis of the effect of spurious modes on beam propagations schemes is performed. Computational convergence and stability tests for the new beam propagations schemes as well as the conventional schemes are presented (AU)