Retrieval of Effective Parameters for Pseudo Chiral Metamaterials
Date Issued
2015
Date
2015
Author(s)
Liao, Yu-Jie
Abstract
Artificial meta-materials is subwavelength periodic structures which exhibit unusual electromagnetic response such as negative refractive index and negative permeability. Subwavelength structure, a structure unit which is smaller than wavelength and it can be analyzed by the effective medium theory which the structure can be regarded as an isotropic or anisotropic effective medium and be described by retrieval of the effective parameters of meta-materials. In this thesis we derive dispersion relation, eigenwaves and impedance based on different sets of constitutive relations through Maxwell equation. Also we derive reflection and transmission coefficients through multiple planer interfaces. Then we use impedance, index of refraction, reflection and transmission coefficients to retrieve the effective parameter of meta-materials. In particular, we study plane wave propagation in a special kind of bi-anisotropic medium: pseudo chiral medium. Because of its special structure, constitutive relations of pseudo chiral medium is more complex than isotropy or anisotropy medium and is more difficult to retrieve due to a lot of unknown effective parameter. So the scattering parameters in three propagation direction are used and we derive dispersion relation, impedance and index of refraction. Then we use impedance, index of refraction, reflection and transmission coefficients from numerical simulation to retrieve the effective parameter of pseudo chiral meta-material. There are two eigenmode in each direction, TE mode and TM mode. Analytical inversion equations are derived in order to retrieve the effective parameter are different in two modes in which we can use two to verify the retrieval of effective parameter. Finally, we change the size of pseudo chiral meta-material like width, thickness, and the radius to analyze the effect of chiral meta-material and find the best parameter to design the material.
Subjects
Subwavelength structure
Meta-material
Effective Medium Theorem
Retrieval of effective parameter
Pseudo-chiral medium.
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-104-R02543056-1.pdf
Size
23.54 KB
Format
Adobe PDF
Checksum
(MD5):e7a16f035a098f5fadea371eebc239d1