Designing the properties of dispersion-flattened photonic crystal fibers

We present a systematic study of group-velocity-dispersion properties in photonic crystal fibers (PCF's). This analysis includes a thorough description of the dependence of the ber geometrical dispersion on the structural parameters of a PCF. The interplay between material dispersion and geometrical dispersion allows us to established a well-defined procedure to design specific predetermined dispersion pro les. We focus on flattened, or even ultraflattened, dispersion behaviors both in the telecommunication window ( around 1.55 mum) and in the Ti-Za laser wavelength range ( around 0.8 mum). We show the different possibilities of obtaining normal, anomalous, and zero dispersion curves in the above frequency domains and discuss the limits for the existence of the above dispersion profiles. (C) 2001 Optical Society of America.