Comparing the plasmon dispersion in graphene and MoS2 nanoribbons array under Electromagnetic excitation

Abstract

Terahertz properties of different materials have been recently studied due to their wide applications in optoelectronics, industry, product inspection, and spectroscopy. Terahertz frequency applications are promising for the medical field as they are considered safe frequencies. Previous terahertz plasma response focused on 2D materials like graphene and transition metal dichalcogenides (TMDs) due to their favourable electronic properties, high electric conductivity, and their band gap characteristics, so they can be used in electronic devices. Some of these materials showed good biocompatibility so they can be used in biomedical applications. Since graphene has zero band gap, researchers are continuously exploring methods to increase its band gap to be used in electronics. Graphene heterostructures or metamaterials are ways to enhance graphene characteristics for specific applications. This work investigates the possibility of using MoS2 with graphene in THz applications. The plasmon dispersion for graphene and MoS2 nanoribbon array structure is compared. Both graphene and MoS2 behave differently in response to terahertz radiation due to their different band gaps. The results showed that MoS2 exhibits a plasmonic response in the THz region at high carrier concentrations. This opens up opportunities for MoS2 to be employed in THz sensors, both independently and in conjunction with graphene within heterostructures or metamaterials for power sources and detectors. These advancements hold significant potential for the future THz imaging and communication technologies.