Din Chai Tee

Photonic Crystal Fiber in Photonic Crystal Fiber for Residual Dispersion Compensation Over

A photonic crystal fiber in photonic crystal fiber (PCF-in-PCF) architecture is numerically investigated for residual dispersion compensation in optical transmission link. The optimized structure shows a flattened and high average dispersion of -457.4 ps/nm/km in the wavelength range of 1360 nm to 1690 nm. The sensitivity of the fiber dispersion properties to a ±2% variation in the optimum parameters is studied for practical conditions. Additionally, the effect of variation in the structure parameters on effective mode area is simulated to understand its relationship to light confinement.

{\rm E} + {\rm S} + {\rm C} + {\rm L} + {\rm U}

We propose a wide angle, efficient and low loss 1 × 3 power splitter based on triangular lattice air holes silicon slab Photonic Crystal (PhC). Desired power splitting ratio was achieved by altering the structure at the junction area of the power splitter. Simulation results obtained using 2-D finite difference time domain method show that for TE polarization incident signal, the power is distributed almost equally with total normalized transmission of 99.74% and negligible reflection loss at the 1550 nm optical operating wavelength. In addition, the power splitter can operate at 1388 nm and 1470 nm optical wavelengths.

Wavelength Bands

We propose a photonic crystal slab-based 1 × 3 power splitter with high output transmission and equal power distribution. It is designed by cascading an asymmetric 1 × 2 power splitter and a symmetric 1 × 2 power splitter. Desired equal power splitting is achieved by introducing and optimizing the splitting region of the 1 × 2 power splitters with flexible structural defects. Simulations were carried out by using 3-D Finite Difference Time Domain method showing equal normalized power distributions of 29.6%, 28.9% and 30.5% at 1550 nm optical wavelength. In addition, equal power splitting also takes place at 1561 nm.

Efficient, Wide Angle, Structure Tuned 1

This paper reports the fabrication and preliminary characterization of optical Flat Fibers. Unlike normal optical fibers which are basically cylindrical waveguides, Flat Fibers are ribbon-like planar samples, opening the possibility of extended length, fully flexible substrates. The fabrication of the Flat Fiber is performed by applying vacuum to a hollow silica preform during the fiber drawing process. Different vacuum settings are used in order to determine the optimum conditions. Other parameters that affect the fiber drawing process are preform feed speed and fiber drawing speed. Preliminary geometrical characterization results confirmed that the experiment (as a proof of principle) successfully produced Flat Fibers. Future work includes more detailed characterization such as determining the optical, mechanical and transmission characteristics of the Flat Fiber.

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Abstract In this work, a modified photonic crystal fibre (PCF) that we refer to as Sunny PCF with enhanced evanescent field exposure structure is proposed. The Sunny PCF with triangular interstitial air holes surrounding the core region increases the interaction of the guided mode with the air. Full-vectorial finite element method with perfectly matched layer boundary condition is used to design and simulate the sensitivity and confinement loss characteristics of the proposed Sunny PCF. By adding sunny structure to a conventional PCF with air-filling ratio of 0.9, the highest achievable sensitivity with negligible confinement loss can be boosted up to 21.23% from 15.83% at the operating wavelength of 1550 nm. Sunny PCF can achieve the same sensitivity as suspended-core holey fibre with lower confinement loss. A preliminary Sunny PCF has been fabricated to prove the feasibility of the proposed structure.

3 Photonic Crystal Power Splitter at 1550 nm for Triple Play Applications

We numerically studied a high-output-transmission-efficiency low-reflection-loss 120° photonic crystal (PhC) waveguide bend based on a PhC slab with triangular-lattice air holes. The desired high output transmission efficiency was achieved by introducing flexible structural defects into the bend region of the waveguide. Simulation results obtained using a 3-D finite-difference time-domain method indicated that normalized output transmission as high as 94.3% and negligible normalized reflection loss of 0.1% were obtained at the 1550-nm optical wavelength. Furthermore, the normalized output transmission was more than 90% within the entire optical C-band. In addition, sensitivity of the design parameters of the structural defect was studied to understand the tolerance in the fabrication error, while maintaining high output transmission efficiency.

Numerical investigation on cascaded 1 × 3 photonic crystal power splitter based on asymmetric and symmetric 1 × 2 photonic crystal splitters designed with flexible structural defects

We numerically studied ZrF 4 -BaF 2 -LaF 3 -AIF 3 -NaF (ZBLAN) photonic crystal fiber (PCF) for potential implementation in optical communication within a 2to 3-μm midinfrared wavelength region. We focused on solid-core uniform air-hole-size hexagonal lattice ZBLAN PCF. The fundamental characteristics such as normalized frequency, confinement loss, chromatic dispersion, effective mode area, and nonlinearity were simulated through a full-vectorial finite-element method with perfectly matched layer boundary condition. Two different structural design ZBLAN PCFs with nonuniform airhole size were designed with zero dispersion wavelength shifted to 2.5 μm. In addition, a near-zero flattened chromatic dispersion ZBLAN PCF within a 2to 3.5-μm wavelength region was achieved. Furthermore, the sensitivity of the dispersion properties to a ±2% variation in the optimum parameters is studied for fabrication tolerance.

Fabrication and characterization of Flat Fibers

In this paper we calculate the dispersion values of our home-made solid core photonic crystal fiber (PCF) based on step index fiber model. Material dispersion and waveguide dispersion is taken into account while carrying out the calculation. The dispersion values predicted by this model agree well with that obtained by a commercial finite element method (FEM) solver.