Ultra-Compact Power Splitter Based on Coupled Surface Plasmons

A novel power splitter based on coupled surface plasmons (SPs) is proposed for optical frequency applications. This power divider is an ultra-compact forward or co-directional coupling device. A specific SiO
₂
-Ag-SiO
₂
685-THz design is demonstrated by full-wave analysis, where a coupling length of only 36 nm and an overall dimension of around 500 nm is achieved. The underlying principle of coupled SPs may lead to various novel nanoscale optical devices.