Analysis of the spectral index method for vector modes of rib waveguides

Abstract

The spectral index method is a new and simple way of finding quickly and easily the guided modes and propagation constants of semiconductor rib waveguides. Here, the method itself is analysed, and its accuracy as compared with finite-difference results is confirmed. Even in its simplest form, the method produces accurate propagation constants and E or H field profiles using little CPU time and negligible storage.