1. Design of a wavelength demultiplexer based on a parabolically tapered multimode interference coupler
- Author
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Xiao, Jinbiao and Sun, Xiaohan
- Subjects
- *
WAVEGUIDES , *OPTICAL communications , *NUMERICAL analysis , *PHOTONICS - Abstract
Abstract: A compact wavelength demultiplexer is designed for the operation at 1.30 and 1.55μm wavelengths using the three-dimensional semi-vectorial beam propagation method. The parabolically tapered multimode interference (MMI) coupler based on the deep-etched SiO2/SiON rib waveguide is introduced into the present demultiplexer for reducing the length. The numerical results show that a MMI section of 330.0μm in length, which is only 76% length of a straight MMI coupler, is achieved with the contrasts of 42.3 and 39.2dB in quasi-TE mode, and 38.4 and 37.8dB in quasi-TM mode at wavelengths 1.30 and 1.55μm, respectively and the insertion losses below 0.2dB. The modified finite difference scheme is applied to approximate the resulting equations along the transverse directions, in which the discontinuities of the derivatives of magnetic field components H y and H x along the vertical and horizontal interfaces, respectively, are involved. [Copyright &y& Elsevier]
- Published
- 2008
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