Performance of metamaterials designed using chaotic fractal structures in signal absorber and sensor applications

Metamaterials are artificial materials that are not found in nature and have unusual electromagnetic properties. They have applications in many fields such as medical, image processing, signal absorption, invisibility cloaks, energy harvesting, sensors and antennas. Chaos theory can be defined as the order of disorder, which is highly sensitive to initial conditions and has a wide power spectrum like noise. By utilising this feature of chaos theory, the resonator layer in metamaterial design is formed from chaos patterns. Chaotic patterns consist of units with both random shapes and dimensions. In this thesis, metamaterial based sensors and absorbers are discussed and simulation studies are carried out. The designed metamaterial consists of three layers: resonator layer, dielectric layer and conductive layer with chaotic patterns. In the sensor application operating in the C band of the spectrum, the pattern obtained from the Rossler chaotic attractor was used in the resonator layer. In the absorber application operating in the infrared region of the spectrum, the pattern obtained from the Lorenz chaotic attractor is used. Simulation studies were carried out using the FIT-based CST Microwave Studio programme. The resonator structure used in the proposed structure has shown similar results with the studies in the literature. Rogers RT5870 material was used as substrate in the signal absorber design and FR-4 material was used in the sensor design. It is predicted that the metamaterials designed within the scope of this thesis can be used in many fields.