On the use of PML for the computation of leaky modes

Purpose The purpose of this paper is to present a complete analysis of leaky modes within a microstructured optical fibre (MOF). Some new numerical results illustrating the versatility and accuracy of our approach are to be given. Design/methodology/approach A method involving both finite elements and perfectly matched layer (PML) is proposed. Findings A rigorous definition of the leaky modes is proposed that leads to a proof of the validity of the PML approach together with a rule for the choice of the PML parameters. Originality/value The choice of parameters associated with the PML are discussed in great detail. The accuracy of the constant of propagation (and especially the imaginary part) are highlighted.