In this paper, we have utilized Au nanoring chains in an host to design certain -and -structures, and expanded it to transport and split the electromagnetic energy in integrated nanophotonic devices operating at an optical communication band (). We compared two structures and tried to choose the best one, with lower losses and higher efficiency at the output branches, in order to split and transport the optical energy. Comparing the different types of nanoparticles corroborates that nanorings have an extra degree of tunability in their geometrical components. Meanwhile, nanorings show strong confinement in near-field coupling, less extinction coefficient, and also lower scattering into the far field during energy transportation at the C-band spectrum. Due to the nanoring’s particular properties, transportation losses would be lower than in other nanoparticle-based structures like nanospheres, nanorods, and nanodisks. We demonstrate that Au nanorings surrounded by an host yield suitable conditions to excite surface Plasmons inside the metal. Comparison between -and -splitters shows that the -splitter is a more suitable alternative than the -splitter, with higher transmission efficiency and lower losses. In the -structure, the power ratio (time-averaged power across the surface) is 24.7%, and electromagnetic energy transportation takes place at group velocities in the vicinity of 30% of the velocity of light; transmission losses are and . In this work, we have applied the finite-difference time-domain method (FDTD) to simulate and indicate the properties of structures.
© 2012 Optical Society of America