Abstract

The formation of the solitons owing to self-phase modulation (SPM) occurs at relatively small intensities [1]. In this cases the transverse team profite may be considered as very close to the spatial profile of the fundamental mode. For shorter pulses or larger intensity when n₂I/Δn≅I (n₂I is the nonlinear part of refraction index, Δn is She difference of core and cladding index) it is needed to include into consideration other thild-order effects such as self-focusing (SF) [2]. For the pulse parameters control it is interesting to investigate the transmission of the ultra-short pulses in periodical waveguides. In the step-index waveguides the transverse structure of fields is strongly dependent from excitation of modes of continuous spectrum of transverse wavenumber, and it is useful to derive the corresponding expressions.

© 1991 Optical Society of America