The paper reports new results of chromatic dispersion in Photonic Crystal Fibers (PCFs) through appropriate designing of index-guiding triangular-lattice structure devised with a selective infiltration of only the first air-hole ring with index-matching liquid. Our proposed structure can be implemented for both ultra-low and ultra-flattened dispersion over a wide wavelength range. The dependence of dispersion parameter of the PCF on infiltrating liquid indices, hole-to-hole distance and air-hole diameter are investigated in details. The result establishes the design to yield a dispersion of 0±0.15ps/ (nm.km) in the communication wavelength band. The designed proposed pertaining to infiltrating practical liquid for near-zero ultra-flat dispersion of 0±0.48ps/ (nm.km) achievable over a bandwidth of 276-492nm in the wavelength range of 1.26μm to 1.80μm.
Herein, we present and compare our spectroscopic results on femtosecond (fs) laser irradiated polymers Poly Methyl Methacrylate (PMMA), Poly Di Methyl Siloxane (PDMS) with crystal media such as Lithium Niobate (LiNbO3). Dependence of the structure width with irradiation dose and scan speed is illustrated. Keldysh parameter calculations are highlighted to describe the dominant ionization process. Formation of micro-craters at low irradiation dose and high scan speed is analyzed through minimal pulse to pulse overlap. Formation of defects such as optical and paramagnetic centers in case of polymers is compared with the absence of such defects in crystal media. Confocal micro-Raman studies carried out on polymers and crystal are presented.