Fast and accurate analysis of three-dimensional structures involving near-zero-index materials

Date

2019-09-01

Author

Karaosmanoglu, Bariscan
Koyaz, Yesim
İbili, Hande
Ergül, Özgür Salih

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We present efficient and accurate frequency-domain analysis of three-dimensional structures involving near-zero-index (NZI) materials with very small permittivity and/or permeability values. Accurate simulations are required to analyze these homogenized models that represent metamaterials with exotic NZI properties, which can be useful in a plethora of applications. When traditional solution methods are directly applied, however, instability and inaccuracy issues arise, making solutions inefficient and inaccurate particularly when electrically large models need to be studied. Identifying that numerical problems are due to unbalanced equations, extremely small/large terms, as well as the traditional low-frequency breakdown, we develop alternative implementations based on novel surface integral equations and broadband multilevel fast multipole algorithm. Numerical examples demonstrate excellent accuracy, stability, and efficiency of the developed solvers for NZI structures.

Subject Keywords

Integral-Equation, Scattering, Surface

URI

https://hdl.handle.net/11511/39036

DOI

https://doi.org/10.1109/iceaa.2019.8879249

Collections

Department of Electrical and Electronics Engineering, Conference / Seminar

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Citation Formats

B. Karaosmanoglu, Y. Koyaz, H. İbili, and Ö. S. Ergül, “Fast and accurate analysis of three-dimensional structures involving near-zero-index materials,” 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39036.