QUASI-PHASE MATCHING IN AN OPTICAL-FIBER WITH PERIODIC BIREFRINGENCE

The propagation of light in a polarization-preserving optical fiber wi th a periodically induced birefringence is analyzed theoretically and investigated experimentally. Regions of quasi-phase-matched four-wave mixing are predicted on the basis of an analysis of the light amplitud e fluctuations and full numerical simulations. The experimental result s are in good agreement with the theoretical analysis, including the e ffect of external variation in the birefringence. The process, generat ed in an optical fiber having an induced periodic birefringence, is si milar to that used for second-harmonic generation in a chi((2)) wavegu ide and for modulational instability in optical fibers with periodical ly varying group-velocity dispersion. (C) 1997 Optical Society of Amer ica.