Abstract

Photonic crystal fibers have opened interesting new ways for guiding ultrashort laser pulses. Hollow-core fibers (HCF) [1] enable guiding of short light pulses at significantly reduced nonlinearities, which avoids nonlinear distortions to the extent possible. The latest generation of these fibers exhibits remarkably low losses, which suggests HCFs as the ideal choice for femtosecond beam delivery. However, with their strongly resonant periodic cladding, HCFs display an awkward third-order dispersion characteristic, strongly distorting sub-100 fs pulses already after a few ten centimetres of propagation. In the following, we demonstrate chirped photonic crystal fibers (CPCFs [2]) as an alternative for guiding ultrashort pulses, widely avoiding the detrimental dispersion properties of HCFs with strictly periodic cladding.

© 2009 IEEE