Transmission properties of fishnet structure as a left handed metamaterial

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2009
Bilge, Şerafettin
Left handed metamaterials are one of the most populer topic attracting attentions of scientists nowadays. Metamaterials are engineered materials which can possess inordinary properties when compared with common materials existing in nature. The main structure investigated in this thesis is fishnet metamaterial which is a left handed metamaterial. Firstly some left handed metamaterials and their properties are surveyed. A retrieval procedure in order to obtain permittivity, permeability and refractive index of any periodic material was summarized. Left handedness of fishnet structure was investigated and proven numerically. Effects of change in polarization of an incoming wave to symmetric and asymmetric fishnet structure were searched. A parametric analysis of fishnet structure was done. Phase advance in a three layered fishnet structure was investigated and compared with phase advance in an ordinary material. Fishnet wedge structure was surveyed and negative refraction and negative phase advance in this structure are shown. Finally, some types of disorderness of fishnet structure, then its effects on transmission results and retrieval results are demonstrated. In order to obtain transmission and reflection through a material, CST Microwave Studio® was used. A code following a numerical procedure in order to retrieve constitutive parameters of a periodic structure which was written in Matlab® was used in this thesis.

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Citation Formats
Ş. Bilge, “Transmission properties of fishnet structure as a left handed metamaterial,” M.S. - Master of Science, Middle East Technical University, 2009.