[摘要]：A fluorine-doped trench-assisted structure is proposed to improve the nonlinearity of photonic crystal fibers (PCFs). Three all-solid highly nonlinear PCFs with low dispersion slope and low confinement loss are designed. They exhibit all normal dispersion, two zero dispersion wavelengths (ZDWs) and one ZDW just at 1.55 mu m, respectively. The lowest dispersion slope is 5.12 x 10(-4) ps/(km . nm(2)), which is 2 orders of magnitude lower than that of conventional highly nonlinear fibers. A nonlinear coefficient of 31.5 W-1 . km(-1) and low loss of 9.62 x 10(-5) dB/km at 1.55 mu m has been achieved for this PCF. (C) 2012 Optical Society of America
