Abstract

It is well known that the propagation in periodic media (e.g., distributed feedback) exhibits forbidden gaps centered around the Bragg frequencies. In the presence of Kerr-like nonlinearities, energy localization in the form of gap or Bragg solitons takes place inside (or close to) the bandgaps.^1-5 Their experimental evidence has been recently reported in an index-modulated fiber.⁴ Although the mechanism of localization in Kerr media is well understood, the possibility of localization for multiple carrier frequencies via different nonlinear mechanisms is intriguing. Here we show that second-harmonic generation (SHG) offers the capability of observing symbiotic energy trapping at fundamental and harmonic carriers, provided they are both dose to (different) Bragg resonances.

© 1997 Optical Society of America