Design of an ultra-flattened negative dispersion elliptical spiral photonic crystal fiber with high nonlinearity and high birefringence

Novel elliptical spiral photonic crystal fiber(PCF) having ultra-flattened negative dispersion, high nonlinearity and high birefringence is proposed. The finite element method is used to optimize the guiding properties. This design provides negative dispersion that is ultra-flattened within range of wavelength from 1385 nm to 1990 nm with deviation of ± 1.5 ps/nm/km. Dispersion value of −93.577 ps/nm/km at 1550 nm wavelength is achieved. The numerical results also indicate the birefringence up to order of 10−2 and nonlinear coefficient of (678.264, 763.485) W−1km−1 at 1550 nm wavelength for fundamental X and Y polarized modes.