design of single mode photonic crystal fiber with outstanding characteristics of confinement loss and chromatic dispersion over s to l communication band

In this article, a novel structure of photonic crystal fiber with nearly zero ultraflattened chromatic dispersion and ultra-low confinement loss is presented. by replacing the circular air-holes of two first rings with the elliptical air-holes, a fiber with outstanding features of chromatic dispersion and confinement loss is designed. the proposed structure is optimized for operating in a wide wavelength range covering s, c, and l communications bands. finite difference frequency domain (fdfd) solver is applied to analyze the proposed fiber components. the designed fiber exhibits a chromatic dispersion of -0.12 ps/nm/km at 1.55 μm along with a slope of 0.002 ps/nm²/km. also, the other remarkable feature of this fiber is ultra-low confinement loss in order of 10^-5 db/km around λ = 1.55 μm.