Finite element based beam propagation modal solution of optical waveguide problems

In this paper, the problem of the accurate calculation of the full vectorial modes in general optical waveguides is addressed. Based on the versatile finite element method, an imaginary axis beam propagation method (IDVFEBPM) is formulated as a means for an efficient and elegant mode solver. The high numerical accuracy of the proposed modal analysis is demonstrated through the analysis of different linear, complex and leaky modes in 3D optical waveguides.