Full-Wave Computational Analysis of Optical Chiral Metamaterials

Guler, Sadri
Solak, Birol
Gür, Uğur Meriç
Ergül, Özgür Salih
We present computational analysis of optical chiral metamaterials that consist of helical metallic elements. At optical frequencies, metals are modeled as penetrable objects with plasmonic properties. A rigorous implementation based on boundary element methods and the multilevel fast multipole algorithm is used for efficient and accurate analysis of three-dimensional structures. Numerical results demonstrate interesting polarization-rotating characteristics of such arrays with helical elements, as well as their complex responses depending on geometric parameters.


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Fast and accurate solutions of electromagnetic scattering problems involving lossy dielectric objects are considered. Problems are formulated with two recently developed formulations, namely, the combined-tangential formulation (CTF) and the electric and magnetic current combined-field integral equation (JMCFIE), and solved iteratively using the multilevel fast multipole algorithm (MLFMA). Iterative solutions and accuracy of the results are investigated in detail for diverse geometries, frequencies, and con...
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Computational simulation and realization of three-dimensional metamaterials with various exotic properties
İbili, Hande; Ergül, Özgür Salih; Department of Electrical and Electronics Engineering (2019)
In this study, computational analysis and realization of three-dimensional metamaterial structures that induce negative and zero permittivity and/or permeability values in their host environment, as well as plasmonic nanoparticles that are used to design metamaterials at optical frequencies are presented. All these electromagnetic problems are challenging since effective material properties become negative/zero, while numerical solvers are commonly developed for ordinary positive parameters. In real life, t...
Accurate solutions of scattering problems involving low-contrast dielectric objects with surface integral equations
Ergül, Özgür Salih (2007-11-16)
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Modified Combined Tangential Formulation for Stable and Accurate Analysis of Plasmonic Structures
Karaosmanoglu, Bariscan; Ergül, Özgür Salih (2019-05-01)
We consider a modified combined tangential formulation (MCTF) for stable and accurate analysis of plasmonic problems involving metallic objects modeled as penetrable bodies. For a wide range of negative real permittivity values, corresponding to varying characteristics of metals at THz, infrared, and visible frequencies, MCTF provides accurate solutions in comparison to the conventional formulations for penetrable objects. We further show that, for structures with subwavelength dimensions, penetrable models...
Citation Formats
S. Guler, B. Solak, U. M. Gür, and Ö. S. Ergül, “Full-Wave Computational Analysis of Optical Chiral Metamaterials,” 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/52741.