Numerical analysis of a novel straight polymer channel waveguide based variable optical attenuator

Abstract

Variable optical attenuators (VOAs) play an important role in the wavelength division multiplexed (WDM) telecommunication networks. It is often necessary to use VOAs to perform functions as: (a) Dynamic channel balancing at MUX location; (b) Dynamic channel leveling at add/drop sites; (c) Receiver overload control; and (d) Optical channel blocking. In order to minimize the overall costs and optimize the performances, VOAs are sometimes required to be integrated with other optical components, such as a MUX/DEMUX, a detector array and etc. Planar lightwave circuit (PLC) technology is the ideal technology platform for realizing this type of large-scale integrations. In this work, we propose a VOA design based on a simple straight polymer channel waveguide layout in order to provide the optimal optical performances with very low electric power consumptions and high fabrication yield. The fabrication of the proposed design will be in compatible with other polymer components on the same substrate. It is found from the simulation results that the design can offer high attenuation level with very low electrical power consumption. In addition, the simulation results demonstrate that the proposed VOA design can achieve very low polarization dependent loss and very good spectra flatness. All these performances would make the proposed VOA design very suitable for large-scale integration applications.