Investigation of continuum generation in the non-zero dispersion-shifted fiber pumped by femtosecond nanojoule pulses in 1450–1800 nm spectral range

Abstract

A synchronously pumped optical parametric oscillator based on periodically poled potassium titanyl phosphate (PPKTP) crystal delivering femtosecond nanojoule energy pulses in the 1.45 μm–1.8 μm spectral range is used as pump source for continuum generation in conventional non-zero dispersion shifted optical fiber. Detailed numerical simulations and experiments employing cross-correlation frequency-resolved optical gating (XFROG) reveal soliton and dispersive wave generation dynamics and can help to estimate limits of how far the pump wavelength can be shifted from zero-dispersion wavelength (ZDW) to still obtain sufficient spectrum broadening. We also demonstrate the applicability of recently introduced fiber dispersion measurement technique based on XFROG trace analysis to conventional optical fibers. Combination of this efficient parametric device with standard non-zero dispersion shifted low cost and low loss optical fiber results in efficient continuum generation with output/input average power ratio greater than 50%.