Dual-concentric-core all-solid photonic bandgap fiber with large dispersion

We propose a novel design of dual-concentric-core all-solid photonic bandgap fiber (DCC-AS-PBGF). It is designed by introducing a ring of bigger high-index rods, a new defect, in the cladding of a conventional all-solid PBGF. Using plane wave expansion method (PWEM) and full-vector finite-element method (FEM), we study the effect of introducing such a ring of bigger high-index rods. The numerical results show that large dispersion is gained around the wavelength where the modes in the new defect couple with the modes in the core. More importantly, the confinement loss of the LP01 modes around the wavelengths, where large dispersion is induced, could be decreased by increasing the rings of high-index rods for the fact that these waveband are within the bandgap.