An enhanced effective mode area fluorine doped octagonal photonic crystal fiber with extremely low loss

In our paper an enhanced effective mode area octagonal photonic crystal fiber (PCF) is presented. This PCF ensures large effective mode area along with ultra-low confinement loss and bending loss. Both the elimination of air-holes from the rings near the core region and inclusion of low index fluorine doped silica rods in an octagonal pattern are the vital design features. We have used full vectorial finite element method (FEM) based software with circularly perfectly matched layer (PML) to simulate the guiding properties of PCF. Our proposed fiber achieves effective mode area of 1110 μm². Moreover, it offers ultra-low confinement loss of 1.14 × 10^-15 dB/m and can be bent as small as 30 cm without any significant bending loss of 6.49 × 10^-9 dB/m. The PCF also ensures low non-linearity with small amount of splice loss. However, our proposed PCF can be used in applications like fiber amplifiers and lasers.