UCLA

In this thesis, we focus on graphene-based surface plasmon-polaritons at terahertz frequencies and their possible applications. The primary motivation is to efficiently couple free-space terahertz radiation into an ultra-compact and low-loss waveguide. Characteristics of surface plasmon-polaritons on monolayer and double-layer graphene are first re-derived and reviewed. Then we propose two novel waveguide structures: graphene-metal structure and graphene-wrapped fibers. Possible modes that can be supported by the structures are analyzed and how to excite them is addressed. Also, promising applications are briefly described. Our work reveals that graphene-metal structure is a good starting point for exploration of both new physics and innovative devices, and that graphene-wrapped fibers can also be of substantial interest as the quality of graphene is improved.