Homogenization of Microwave Metamaterial Structures Using Full-Wave Solutions and Genetic Algorithms

Metamaterials involve small details that create challenges in their numerical analysis. As commonly practiced, homogenization of such complex structures may simplify and facilitate their numerical solutions. However, homogenization should be performed carefully to avoid excessive modeling errors, especially for finite structures. In this paper, we present accurate homogenization of three-dimensional metamaterials involving split-ring resonators (SRRs). Electromagnetic characteristics of finite SRR structures are found by rigorous optimization via genetic algorithms, while necessary numerical simulations are accurately performed by using the multilevel fast multipole algorithm. The results demonstrate the promising effectiveness of the approach for realistic metamaterial structures.


Electromagnetic modeling of split-ring resonators
Gurel, Levent; Unal, Alper; Ergül, Özgür Salih (2006-09-15)
In this paper, we report our efforts to model split-ring resonators (SRRs) and their large arrays accurately and efficiently in a sophisticated simulation environment based on recent advances in the computational electromagnetics. The resulting linear system obtained from the simultaneous discretization of the geometry and Maxwell's equations is solved iteratively with the multilevel fast multipole algorithm. As an example, we present an array of 125 SRRs showing a negative effective permeability about 92 GHz.
Rigorous Analysis of Deformed Nanowires Using the Multilevel Fast Multipole Algorithm
Karaosmanoglu, Bariscan; Yilmaz, Akif; Ergül, Özgür Salih (2015-05-17)
We present accurate full-wave analysis of deformed nanowires using a rigorous simulation environment based on the multilevel fast multipole algorithm. Single nanowires as well as their arrays are deformed randomly in order to understand the effects of deformations to scattering characteristics of these structures. Results of hundreds of simulations are considered for statistically meaningful analysis of deformation effects. We show that deformations significantly enhance the forward-scattering abilities of ...
Computational design of nanoantennas with improved power enhancement capabilities via shape optimization
Işiklar, Göktuǧ; Yazar, Şirin; İbili, Hande; Onay, Gülten; El Ahdab, Zeina; Ergül, Özgür Salih (2023-01-01)
Computational design and analyses of nanoantennas obtained via surface shape optimization are presented. Starting with a kernel geometry, free deformations are applied on selected surfaces to reach optimal designs that can provide improved power enhancement capabilities at desired frequencies. An in-house implementation of genetic algorithms is efficiently combined with the multilevel fast multipole algorithm developed for accurate solutions of plasmonic problems to construct the effective optimization envi...
Efficient and Accurate Electromagnetic Optimizations Based on Approximate Forms of the Multilevel Fast Multipole Algorithm
Onol, Can; Karaosmanoglu, Bariscan; Ergül, Özgür Salih (2016-01-01)
We present electromagnetic optimizations by heuristic algorithms supported by approximate forms of the multilevel fast multipole algorithm (MLFMA). Optimizations of complex structures, such as antennas, are performed by considering each trial as an electromagnetic problem that can be analyzed via MLFMA and its approximate forms. A dynamic accuracy control is utilized in order to increase the efficiency of optimizations. Specifically, in the proposed scheme, the accuracy is used as a parameter of the optimiz...
Computational Design of Optical Couplers for Bended Nanowire Transmission Lines
Tuncyurek, Yunus Emre; Karaosmanoglu, Bariscan; Ergül, Özgür Salih (2017-07-01)
We present computational analysis, optimization, and design of optical couplers that can be useful to improve the transmission along bended nanowires. After demonstrating the deteriorated energy transmission due to sharp bends, which lead to out-of-phase nanowires and diffraction, we use a rigorous simulation environment to design efficient couplers made of spherical particles. For this purpose, an optimization module based on genetic algorithms is combined with the multilevel fast multipole algorithm, lead...
Citation Formats
H. İbili and Ö. S. Ergül, “Homogenization of Microwave Metamaterial Structures Using Full-Wave Solutions and Genetic Algorithms,” 2018, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/54181.