In this work, dynamically tunable graphene-based metamaterials with non-symmetrical geometries including chiral and anisotropic metamaterials with much better performances will be proposed, designed, and investigated. Novel dynamically tunable graphene-based metamaterials with non-symmetrical geometries are designed and analyzed. In addition, the circuit model (CM) approach for such dynamically graphene-based metamaterials with non-symmetrical geometries is an ongoing project which are very simple, quick, and fast in MATLAB Software and real world. The main outstanding advantage of the proposed dynamically tunable graphene-based metamaterials is that the output spectra are tunable by just changing the applied bias voltage without the need to refabricate the metamaterials. Moreover, these metamaterials are expected to perform much better in terms of losses, light wave confinement, propagation length, flexibility, and tunability than conventional metamaterials. The main objective of this thesis is to investigate dynamically tunable micro-scale size graphene-based terahertz metamaterials by circuit models in MATLAB Software and simulations in CST Software. 2D and 3D metamaterials with non-symmetrical geometries with desired responses, and the CM approach for these metamaterials with non-symmetrical geometries are in the scope of this thesis, eight papers were published successfully in reputable journals and seven other metamaterials are in progress. Simulations will be performed by MATLAB and CST Software. Circuit modeling is being performed in MATLAB by coding. Simulations of the proposed metamaterials would be performed by finite element method (FEM). Successful results of this research will enhance the understanding of dynamically tunable graphene-based metamaterials by circuit models and lead to novel high-performance terahertz optical metamaterials. These novel dynamically tunable metamaterials can be utilized in different fields of terahertz systems, 6G wireless communications, and telecommunications with excellent performances compared to the typical metamaterials.

2024

2025