Search ETDs:
Novel Metamaterial Blueprints and Elements for Electromagnetic Applications
Odabasi, Hayrettin

2013, Doctor of Philosophy, Ohio State University, Electrical and Computer Engineering.
In the first part of this dissertation, we explore the metric invariance of Maxwell's equations to design metamaterial blueprints for three novel electromagnetic devices. The metric invariance of Maxwell's equations here means that the effects of an (hypothetical) distortion of the background spatial domain on the electromagnetic fields can be mimicked by properly chosen material constitutive tensors. The exploitation of such feature of Maxwell's equations to derive metamaterial devices has been denoted as `transformation optics' (TO). The first device proposed here consists of metamaterial blueprints of waveguide claddings for (waveguide) miniaturization. These claddings provide a precise control of mode distribution and frequency cut-off. The proposed claddings are distinct from conventional dielectric loadings as the former do not support hybrid modes and are impedance-matched to free-space. We next derive a class of metamaterial blueprints designed for low-profile antenna applications, whereby a simple spatial transformation is used to yield uniaxial metamaterial substrate with electrical height higher than its physical height and surface waves are not supported, which is an advantage for patch antenna applications. We consider the radiation from horizontal wire and patch antennas in the presence of such substrates. Fundamental characteristics such as return loss and radiation pattern of the antennas are investigated in detail. Finally, transformation optics is also applied to design cylindrical impedance-matched absorbers. In this case, we employ a complex-valued transformation optics approach (in the Fourier domain) as opposed to the conventional real-valued approach. A connection of such structures with perfectly matched layers and recently proposed optical pseudo black-hole devices is made.

In the second part of this dissertation, we move from the derivation of metamaterial blueprints to the application of pre-defined unit-cell metamaterial structures for miniaturization purposes. We first employ electric-field-coupled (ELC) resonators and complementary electric-field-coupled (CELC) resonators to design a new class of electrically small antennas. Since electric-field coupled resonators were recently proposed in the literature to obtain negative permittivity response, we next propose ELC resonators as a new type of waveguide loadings to provide mode control and waveguide miniaturization.
Fernando Teixeira (Advisor)
145 p.

Recommended Citations

Hide/Show APA Citation

Odabasi, H. (2013). Novel Metamaterial Blueprints and Elements for Electromagnetic Applications. (Electronic Thesis or Dissertation). Retrieved from https://etd.ohiolink.edu/

Hide/Show MLA Citation

Odabasi, Hayrettin. "Novel Metamaterial Blueprints and Elements for Electromagnetic Applications." Electronic Thesis or Dissertation. Ohio State University, 2013. OhioLINK Electronic Theses and Dissertations Center. 25 Nov 2017.

Hide/Show Chicago Citation

Odabasi, Hayrettin "Novel Metamaterial Blueprints and Elements for Electromagnetic Applications." Electronic Thesis or Dissertation. Ohio State University, 2013. https://etd.ohiolink.edu/

Files

dissertation.pdf (2.47 MB) View|Download