Design of a metamaterial absorber operating at terahertz (THz) frequency

Signals in the Terahertz (THz) frequency range have many characteristics, such as high penetration power, application security, high SNR, and minimum transmission loss. Furthermore, thanks to its wider bandwidth, THz frequency radar systems enable higher resolution imaging compared to other radars. Due to these advantages, radar systems operating in the THz frequency band can be more effective in automatic detection and detecting hidden objects. Considering these advantages, it is inevitable that THz radar usage will increase and eventually replace previous radar systems. However, the ability to move without being detected by radar has become crucial, especially in military technology. Under normal circumstances, finding absorptive materials that can provide invisibility against THz radar is quite challenging, as natural materials have a weak effect on THz signals. Metamaterials are artificially engineered materials with modified dielectric properties in laboratory settings. Metamaterials are commonly used in military applications for coating vehicles such as aircraft, ships, and submarines, reducing the probability of being detected by radar systems and achieving the desired invisibility. In this thesis, the focus is on designing an electromagnetic screen that can operate at the Terahertz (THz) level using metamaterials. The purpose of the study is to advance a screen design that can achieve the targeted absorption value. Simulations conducted on the prototype design demonstrate a high absorption rate of 99.98%.