Optimization of nanoparticle arrays to design efficient couplers for plasmonic nanowire networks

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2019
Altınoklu, Aşkın
In this thesis, a novel optimization strategy for design and optimization of efficient couplers to improve nano-optical links in complex plasmonic nanowire networks is presented. Various cases involving alternative combinations of nanowire transmission lines with different types and lengths are considered. As the optimization environment, a full-wave solver based on surface integral equations and the multilevel fast multipole algorithm (MLFMA) developed for efficient and accurate solutions of plasmonic problems is integrated with a heuristic optimization method based on genetic algorithms. Efficient designs of nano-couplers for different isolated scenarios involving bent and straight nanowires are obtained to build large nano-optical systems and networks involving nanowires and optimized nano-couplers. Usage of multiple couplers and their integration on the same transmission line are studied in detail. The performances of the designed couplers are examined in many aspects, including comparisons with the classical approaches known in the literature. In addition to the design of effective nano-couplers to improve optical transmission via nanowire systems, several guidelines and conclusions are provided for the efficient usage of the designed nano-couplers while constructing complex nanowire networks and nano-optical links.

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Citation Formats
A. Altınoklu, “Optimization of nanoparticle arrays to design efficient couplers for plasmonic nanowire networks,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Electrical and Electronics Engineering., Middle East Technical University, 2019.