Transformation Optics Devices From Artificial Dielectrics In Microwave Frequencies

Transformation optics (TO) has become widely appreciated for its ability to designstructures that manipulate waves with unprecedented control. The main tool associatedwith TO is coordinate transformation, in which isotropic space is conceptually warped ordistorted as a mean of guiding trajectories of waves. From coordinate transformation, wecan obtain the required material electromagnetic parameters which are always veryextreme such as anisotropic, inhomogeneous or containing extreme value. This kind ofmaterial is called metamaterials. Metamaterials always own the particular electromagneticproperties which never appear in natural materials, like negative refractive index or exoticrefractive index distribution profile. Metamaterials is not only in theory but also inlaboratory. These artificial metamaterials can be formed by periodic arrangements, such asmetallic mesostructures and split ring resonators, for achieving electromagnetic propertiesthat cannot be found in nature.In recent years, a new structure based on metamaterials, called metasurface, has beena topic. Lots of phenomena such as abnormal refraction and reflection have been found onthis structure based on which researchers have fabricated the device that can transform apropagation wave into a surface wave. In this work, we introduce the origin anddevelopment of the metamaterials including some classical resonance model. To study theelectromagnetic properties of metamaterials, we will introduce some measuring skills inlaboratory such as two-dimentional (2D) near field measurement system and finite elementmethod simulation.There have been some weaknesses in usual coordinate transformation such as narrowband frequency and complex parameters. The parameters from conformal mapping are anisotropic and do not exhibit extreme values. We fabricate a lens based on conformalmapping and artificial dielectrics which can transform a point source into plane wave.The output wave is very collimated and works in a wide frequency regime.Utilizing the metasurface concept, we fabricate an asymmetric waveguide which is aprototype of optical diode.