Accurate analysis of metamaterials involving finite arrays of split-ring resonators and thin wires

2007-03-30
Gurel, Levent
Ergül, Özgür Salih
Unal, Alper
In order to gain physical insight into how some metamaterial structures behave, we report our results obtained by accurate numerical solutions of electromagnetic problems related to various constructions of split-ring-resonators (SRRs) and thin wires (TWs). Single and multiple layers of arrays of SRRs and TWs are investigated in detail using the electric-field integral equation. Without utilizing any homogenization techniques, we accurately model large numbers of unit cells that translate into very large computational problems, which are solved efficiently by employing multilevel fast multipole algorithm.

Suggestions

Optimal Cavities to Enhance Free-space Matching in Solar Cells
Karaosmanoglu, B.; Topcuoglu, U.; Guler, S.; Tuygar, E.; Ergül, Özgür Salih (2018-08-04)
In this paper, we present design and numerical simulations of nano-cavities for free space matching in solar cells at optical frequencies. The cavity designs are inspired by the wellknown antenna geometries that are commonly used at radio and microwave frequencies. Using such designs that have not been explored before in the context of solar cells, the electromagnetic mismatch between solar-cell surfaces and vacuum is significantly reduced, in comparison to planar interfaces and those with the conventional ...
Improved Nano-optical Traps for Single-particle Sensing Applications
Isiklar, G.; Algun, M.; Ergül, Özgür Salih (2019-01-01)
We present numerical design and simulations of nano-optical traps for single-particle sensing applications. While commonly used nano-holes with circular shapes are suitable for physically trapping nanoparticles to be detected and identified, they generate relatively weak signals in the far zone, especially when nanoparticles are small. We show that optical sensitivity of nano-holes can be enhanced significantly by using well-designed tip geometries such that metallic and dielectric nanoparticles can be dete...
Accurate solutions of scattering problems involving low-contrast dielectric objects with surface integral equations
Ergül, Özgür Salih (2007-11-16)
We present the stabilization of the surface integral equationsfor accurate solutions of scattering problems involvinglow-contrast dielectric objects. Unlike volume formulations,conventional surface formulations fail to provide accurateresults for the scatteredfields when the contrast of theobject is small. Therefore, surface formulations are requiredto be stabilized by extracting the nonradiating parts of theequivalent currents. In addition to previous strategies forthe stabilization, we introduce a n...
Analysis of Composite Structures Involving Near-Zero-Index Materials
Koyaz, Yesim; İbili, Hande; Karaosmanoglu, Bariscan; Ergül, Özgür Salih (2019-01-01)
We consider numerical solutions of electromagnetic problems involving near-zero-index materials with permittivity and/or permeability values close to zero. These types of problems are inherently multiscale due to the large variety of the wavelength from very large values to ordinary values in the same problem. In addition to developing a stable formulation for extreme values of the intrinsic impedance, we employ a broadband multilevel fast multipole algorithm based on approximate diagonalization for efficie...
FAST AND ACCURATE ANALYSIS OF LARGE METAMATERIAL STRUCTURES USING THE MULTILEVEL FAST MULTIPOLE ALGORITHM
Guerel, L.; Ergül, Özgür Salih; Uenal, A.; Malas, T. (2009-01-01)
We report fast and accurate simulations of metamaterial structures constructed with large numbers of unit cells containing split-ring resonators and thin wires. Scattering problems involving various metamaterial walls are formulated rigorously using the electric-field integral equation, discretized with the Rao-Wilton-Glisson basis functions. Resulting dense matrix equations are solved iteratively,where the matrix-vector multiplications are performed efficiently with the multilevel fast multipole algorithm....
Citation Formats
L. Gurel, Ö. S. Ergül, and A. Unal, “Accurate analysis of metamaterials involving finite arrays of split-ring resonators and thin wires,” 2007, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/52661.