Design of low dispersion and low loss photonic crystal fiber: Defected core circular-octagon hybrid lattices

Abstract Photonic crystal fibers consisting of a novel hybrid structure providing low values for both dispersion and confinement loss were simulated using finite element method. The studies on different arrangements, polygonal and circular, of air holes as cladding of PCFs have shown that circular PCFs results in a structure with low dispersion, air filling fractions remaining same. Circular PCF with dispersion 103.50 ps/nm.km and confinement loss 5.97 × 10 −6  dB/m was restructured by replacing its first ring with octagonal air hole lattice having eight air holes. This hybrid circular-octagon PCF has shown a dispersion of 33.15 ps/nm.km and a confinement loss of 2.52 × 10 −6  dB/m. The introduction of air hole defects in the hybrid fiber core with three identical air holes in an equilateral triangular lattice was found to modify dispersion by reducing its value to −11.63 ps/nm.km with confinement loss 9.51 × 10 −5  dB/m.