Plasmonics: A route to design an optical demultiplexer based on gold nanorings arrays to operate at near infrared region (NIR)

In this work, a new configuration and orientation of nanoring arrays which are able to couple and guide the plasmon resonance efficiently have been discussed thoroughly. Accordingly, we proposed an efficient demultiplexer which is able to separate two different wavelengths (λ~1550 nm and λ~1310 nm) from one incident signal and route each one of them to the certain and isolated ports (output). To realize this, three nano-arrays of Au rings with specific geometrical sizes were surrounded and filled by a silica (SiO2) substance. The optical properties of the examined device are presented numerically and the operation quality and effect of dissipative components such as cross talk effect and transmission loss factor have been investigated. A Finite-Difference Time-Domain method (FDTD) as a proper numerical simulation model has been employed to extract the characteristics of the device.