Plasmonic surface-wave splitter

The authors present an analysis of a plasmonic surface-wave splitter, simulated using a two-dimensional finite-difference time-domain technique. A single subwavelength slit is employed as a high-intensity nanoscale excitation source for plasmonic surface waves, resulting in a miniaturized light-surface plasmon coupler. With different surface structures located on the two sides of the slit, the device is able to confine and guide light waves of different wavelengths in opposite directions. Within the 15μm simulation region, it is found that the intensity of the guided light at the interface is roughly two to eight times the peak intensity of the incident light, and the propagation length can reach approximately 42 and 16μm and at the wavelengths of 0.63 and 1.33μm, respectively.