Development of highly nonlinear polarization maintaining fibers with normal dispersion across entire transmission window

TL;DR

This paper reports the development of polarization maintaining, highly nonlinear photonic crystal fibers with normal dispersion across the entire transmission window, enabling broad supercontinuum generation for ultrafast nonlinear optics applications.

Contribution

It presents a comprehensive process from simulation to fabrication and characterization of fibers with specific nonlinear and dispersion properties for ultrashort pulse generation.

Findings

Achieved all-normal dispersion profile over the entire transmission window.

Developed fibers support full octave supercontinuum generation.

Fibers are suitable for use with commercially available femtosecond lasers.

Abstract

Determined polarization state of light is required in nonlinear optics applications related to ultrashort and single-cycle light pulse generation. Such short time scales require up to full octave of spectral width of light. Fiber-based, pulse-preserving and linearly polarized supercontinuum can meet these requirements. We report on the development - from linear simulations of the fiber structure, through fabrication of physical fibers to their versatile characterization - of polarization maintaining, highly nonlinear photonic crystal fibers, intended for femtosecond pumping at a wavelength of 1560 nm. Full octave of linearly polarized light around this wavelength would enable to cover amplification bandwidths of the three major fiber amplifiers from ytterbium doped systems up to thulium and holmium doped fiber amplifiers, with a coherent, linearly polarized seed signal. At the same time, an all-normal chromatic dispersion profile over an entire transmission window, and small dispersion of nonlinearity in the developed fibers, would facilitate use of commercially available femtosecond fiber lasers as pump sources for the developed fibers.