In this paper, the RII depressed core triple clad based structure as Zero-dispersion Shifted optical fiber is optimized to obtain small pulse broadening factor (small dispersion and its slope) and low bending loss suitable for long haul communications. The proposed structures allow reducing the dispersion, its slope and the bending loss. The Genetic Algorithm (GA) and the Coordinate Descent (CD) technique are used for the optimization. The suggested design approach involves a special cost function which includes dispersion, its slope, and bending loss impacts. The proposed algorithm and structure have inherent potential to obtain large effective area and extend tolerance of bending loss simultaneously. Meanwhile, an analytical method is used to calculate the dispersion and its slope. In the meantime, the thermal stabilities of the designed structures are evaluated.
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