He. Hernandezfigueroa et al., FINITE-ELEMENT APPROACH FOR THE MODAL-ANALYSIS OF OPEN-BOUNDARY WAVE-GUIDES, Electronics Letters, 30(24), 1994, pp. 2031-2032
A general finite element approach to computing the modes of open-bound
ary waveguides is presented. This efficient and robust scheme applies
equally to situations with real and complex propagation constants. By
using a localised boundary impedance condition, the approach preserves
the sparsity of the global matrices. A comparison with the well estab
lished infinite element technique and the analysis of a 2-D leaky opti
cal structure are given as examples.