Approximation of photonic crystal fibres with large air holes by the step index fibre model

B. Reichel, Keith J. Blow

Research output: Contribution to journalArticle


An equivalent step index fibre with a silica core and air cladding is used to model photonic crystal fibres with large air holes. We model this fibre for linear polarisation (we focus on the lowest few transverse modes of the electromagnetic field). The equivalent step index radius is obtained by equating the lowest two eigenvalues of the model to those calculated numerically for the photonic crystal fibres. The step index parameters thus obtained can then be used to calculate nonlinear parameters like the nonlinear effective area of a photonic crystal fibre or to model nonlinear few-mode interactions using an existing model.
Original languageEnglish
Pages (from-to)1479-1486
Number of pages8
JournalJournal of Modern Optics
Issue number9
Publication statusPublished - May 2008



  • photonic crystal fibres
  • ESI model
  • multimode
  • eigenvalues

Cite this