Structural Optimization of an Optical 90 Degree Hybrid Based on a Weaklyguided 4x4 Multimode Interference Coupler Using a Parallelized Real-coded Micro-genetic Algorithm
Keywords:
Beam-propagation method, finite element method, genetic algorithm, multimode interference coupler, optical waveguides, parallel computationAbstract
The optimal design of a 4x4 multimode interference (MMI) coupler as an optical 90° hybrid based on a weakly-guided optical waveguide was considered. Seven geometrical parameters of a 4x4 MMI coupler were optimized by a real-coded micro-genetic algorithm, and parallelized using a message-passing interface. The beam-propagation method was used to evaluate the fitness of the MMI coupler in the optimization process. The optimized 4x4 MMI coupler showed a common-mode rejection ratio greater than 28.9 dBe and a phase error less than 2.52° across a wavelength range of 1520 to 1580 nm, which satisfied typical system requirements. The optimization process was executed on a Beowulf-style cluster comprising five identical PCs, and its parallel efficiency was 0.78.
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References
Y. Sakamaki, Y. Nasu, T. Hashimoto, K. Hattori, T. Saida, and H. Takahashi, “Reduction of phasedifference deviation in 90º optical hybrid over wide wavelength range,” IEICE Electron. Express, vol. 7, no. 3, pp. 216-221, Feb. 2010.
C. R. Doerr, D. M. Gill, A. H. Gnauck, L. L. Buhl, P. J. Winzer, M. A. Cappuzzo, A. Wong-Foy, E. Y. Chen, and L. T. Gomez, “Monolithic demodulator for 40-Gb/s DQPSK using a star coupler,” J. Lightw. Technol., vol. 24, no. 1, pp. 171-174, Jan. 2006.
L. Zimmermann, K. Voigt, G. Winzer, K. Petermann, and C. M. Weinert, “