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Abstract: A novel polarizer is designed by liquid filling in partial air-holes of a hollow-core photonic bandgap fiber (PBGF) forming an asymmetric waveguide structure, which leads to the vertical polarization light leaking out while the horizontal polarization light remaining to propagate along the fiber with a relatively low loss. Applied with a full-vector finite-element (FEM) method, a series of polarizer structures with different water-filled regions has been simulated for a better performance on the polarization extinction ratio and the insertion loss. Through optimization, the proposed PBGF polarizer has a high polarization extinction ratio of more than 32dB in the operation wavelength range from 1530nm to 1600nm. [Copyright &y& Elsevier]

Abstract: We investigate the dispersion property of space filling mode of photonic crystal structures and find a new type of dispersion—structure induced dispersion. By incorporating this new source of dispersion we designed PCF with large normal dispersion ~350ps2/km. Our simulation indicates the dispersion of such fiber changes less than 3% in 1.4–1.7μm wavelength range and we also show that our design is insensitive to the structure changes. [Copyright &y& Elsevier]

Abstract: In order to save the switching ports and the cost of Multi-Granularity Optical Cross-Connect (MG-OXC), the waveband switching technique was proposed to groom multiple wavelength-level traffic to a few waveband tunnels to be switched by a few switching ports in MG-OXC. At the same time, protection for fibers is very important to ensure the service continuity since each wavelength carries a lot of traffic. Although existing works have addressed the waveband switching protection, most of them separately considered only the dedicated protection or shared protection in static demand scenario and did not deeply analyze and compare the dedicated protection and shared protection in dynamic demand scenario. Therefore, in this paper, we deeply study the consumptions of wavelengths in fibers and ports in MG-OXCs for Waveband Shared Protection (WSP) and Waveband Dedicated Protection (WDP) in dynamic demand scenario, and propose the port-cost calculation and update methods based on a new waveband layered auxiliary graph that is developed based on MG-OXC structure. In simulations, we compare WSP, WDP, traditional end-to-end waveband shared protection and traditional end-to-end waveband dedicated protection. Simulation results show that the shared protection has smaller port-cost, better wavelength utilization efficiency and lower blocking probability than the dedicated protection with the same waveband switching policy, and the sub-path waveband switching has bigger port-cost, better wavelength utilization efficiency and lower blocking probability than the end-to-end waveband switching with the same backup wavelength assignment policy. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we report an analytical modeling of N+-InP/n0-In0.53Ga0.47As/p+-In0.53Ga0.47As p-i-n photodetector for optical fiber communication. The results obtained on the basis of our model have been compared and contrasted with the simulated results using ATLAS™ and experimental results reported by others. The photodetector has been studied in respect of energy band diagram, electric field profile, doping profile, dark current, resistance area-product, quantum efficiency, spectral response, responsivity and detectivity by analytical method using closed form equations and also been simulated by using device simulation software ATLAS™ from SILVACO® international. The photodetector exhibits a high quantum efficiency ∼90%, responsivity ∼1.152–1.2 A/W in the same order as reported experimentally by others, specific detectivity ∼5×109 cmHz1/2 W−1at wavelength 1.55–1.65μm, dark current of the order of 10−11 A at reverse bias of 1.5V and 10−13–10−12 A near zero bias. These values are comparable to those obtained for practical p-i-n detectors. The estimated noise equivalent power (NEP) is of the order of 2.5×10−14 W. [Copyright &y& Elsevier]