Abstract

The photonic crystal fibre (Fig. 1) is a pure silica structure with a solid core surrounded by a hexagonal array of sub-micron air capillaries - the photoniccrystal. One of the unusual properties of the fibre is that it can be single-mode at all wavelengths, as has been confirmed experimentally over the range 337- 1550 nm[1]. This behaviour is due to the unusual wavelength dependence of the effective refractive index of the fibre's photonic crystal cladding[2], which may be expected to have interesting consequences for the guided mode's dispersion. Unfortunately, the simple effective index model is not capable of calculating modal properties like propagation constants, group velocity dispersion and field distributions.

© 1998 IEEE