Design of a Polarization-Maintaining Equiangular Spiral Photonic Crystal Fiber for Residual Dispersion Compensation Over $E{+}S{+}C{+}L{+}U$ Wavelength Bands

An equiangular spiral photonic crystal fiber has been designed and numerically optimized to obtain its residual chromatic dispersion compensation property in the wavelength range of 1350-1675 nm. The results show that the fiber exhibits an average dispersion of -227 ps/nm-km with a flattened dispersion profile. It is also demonstrated that the fiber shows a high birefringence of 0.0221 at the wavelength 1550 nm. An elliptical air hole is introduced as a defect in the core region and this gives an additional flexibility to tailor the dispersion property. The proposed fiber can be used as an excellent candidate in wavelength-division-multiplexing optical fiber transmission system for residual chromatic dispersion compensation and also for maintaining single polarization.