Broadband nearly-zero ultra-flattened dispersion single mode index guiding holey fiber

This paper proposes and demonstrates a novel type of silica index guiding holey fibers (IGHFs) that has two cladding layers at the defective innermost structures. The proposed IGHFs exhibit remarkable chromatic dispersion properties such as nearly-zero and flattened dispersion over a wide spectral range and single mode guidance along with very low confinement loss. The numerical results indicate that 5 air-hole rings of nearly zero ultra-flattened dispersion single mode IGHFs can be designed with desire flattened dispersion of over a 340 nm bandwidth including the entire band of interest with low confinement loss of less than 10⁻⁶ dB/m.