Chromatic dispersion control in photonic crystal fibers: application to ultra-flattened dispersion

Abstract

In order to control dispersion and dispersion slope of indexguiding photonic crystal fibers (PCFs), a new controlling technique of chromatic dispersion in PCF is reported. Moreover, our technique is applied to design PCF with both ultra-low dispersion and ultra-flattened dispersion in wide wavelength range. A full-vector finite element method with anisotropic perfectly matched layers is used to analyze the dispersion properties and the confinement losses in a PCF with finite number of air holes. It is shown from numerical results that it is possible to design a fourring PCF with flattened dispersion of 0 +/- 0.5 ps/(km.nm) from 1.19 m to 1.69 m wavelength range and a five-ring PCF with flattened dispersion of 0 +/- 0.4 ps/(km.nm) from 1.23 m to 1.72 m wavelength range.

Dispersion Tolerance of Various Photonic Crystal Fibers

“…To simulate dispersion characteristics of different PCFs, the FDM with PML boundaries (Saitoh et al 2003) is used in the Cartesian co-ordinates. The background material of the PCFs is pure silica with refractive index 1.45.…”

“…To model the leakage, an open boundary condition has to be used, which produces no reflection at the boundary. PMLs are so far the most efficient absorption boundary condition for this purpose (Saitoh et al 2003). The complex refractive index of the fundamental modes can be solved from the Maxwell's equations as a standard eigenvalue problem with the FDM (Zhu and Brown 2002).…”

“…The material dispersion D m ðkÞ can be obtained directly from the three-term Sellmeier formula (Saitoh et al 2003) and is directly included in the FDM calculation. The waveguide dispersion D g ðkÞ occurs when speed of a wave in a waveguide depends on its frequency and is related to the effective refractive index n eff .…”

“…As a result, control of chromatic dispersion in PCFs has been subjected to numerical and experimental studies for the last ten years. Various index guiding hexagonal PCFs with remarkable dispersion properties (Wu and Chao 2005;Ferrando et al 2000;Ferrando et al 2001;Reeves et al 2002;Poletti et al 2005;Saitoh, Florous, and Koshiba 2005;Saitoh et al 2003) have been reported to date. The fabrication issue, more specifically the fabrication tolerance of these intriguing designs, is also crucial because in a standard fiber draw 1% variation in the fiber diameter occurs unavoidably during the fabrication process (Reeves et al 2002).…”

Bending Analysis of a Dual-Core Photonic Crystal Fiber

“…The appearance of photonic crystal fibers (PCFs) [1][2][3][4][5][6][7][8][9][10] with silicaair microstructure is a milestone in the history of optical fibers, which have achieved excellent optical properties in birefringence [11][12][13][14][15][16], dispersion [17][18][19][20], single polarization single mode [21][22][23][24][25], nonlinearity [26][27][28][29][30], and effective mode area [31][32][33][34][35] over the past several years. It is well known that PCFs have shown excellent performances in applications such as optical communications [36][37][38], fiber lasers [39][40][41][42], supercontinuum sources [43][44][45][46] and also fiber sensors ...…”