Logic Gates of Terahertz Spoof Surface Plasmons

Spoof surface plasmon polariton (SSPP) interconnects have great potential for the next-generation wireless communications and terahertz (THz) integrated circuits. SSPP logic gates are reported to meet the above development requirements. However, the reported SSPP logic gates consist of 3D domino waveguide structure and conversion structure with a funnel-shaped metasurface; and hence, suffer from the size limit of the compact on-chip integrations. To explore a more compact and flexible design, a series of logic gates in the planar THz SSPP platform, including OR, AND, XOR, NOT, and NAND gates, is experimentally demonstrated. Owing to the flexible dispersion behaviors, different phase differences between inputs can be controlled by manipulating the SSPP waveguide structure, such as the SSPP Mach-Zehnder interferometer, thereby realizing various THz SSPP logic gates, which will enable powerful potential in large-scale on-chip systems, future wireless communications, and intelligent computing.