The speed of intra-chip and inter-chip connection is one of the main bottlenecks to achieving faster computer chip performance. Routing the signals through surface-plasmon-based waveguides provides one possible way to achieve faster optical connection speeds; these waveguides are compact, not bound by the diffraction limit, and can be easily integrated with both optical and electronic technologies.
One basic challenge facing the adoption of plasmon guides within electrical chips is the excitation of the plasmons from external sources. Simulating this effect requires a rigorous full-vector modeling environment that provides accurate solutions for arbitrary device geometries containing both metallic and nonmetallic components. FullWAVE FDTD is the ideal tool to meet this need. FullWAVE provides a full-vector solution to Maxwell’s equations and allows engineers to use complex material definitions, arbitrary device geometries, non-uniform grids, and sophisticated measurement techniques to create new plasmonic devices and fine-tune existing designs for specific applications. The design parameters of the structure can also be perturbed in FullWAVE FDTD to allow the study of manufacturing tolerances on device performance.
The surface-plasmon-based spatial multiplexer studied in Figure 1 consists of a multiplexing switch that steers light toward one of several subwavelength metal-strip waveguides. Several 3D FullWAVE FDTD simulations were performed at a fixed wavelength, at various incident angles of the illumination to determine the optimal angles at which light is coupled into each of the three metal-strip waveguides.