Transmissivity Assessment of a Sandwiched MDM Plasmonic Waveguide between two Dielectric Waveguides

Integrating both dielectric and plasmonic waveguides on the same chip is needed for the future of the integration of nanoplasmonic circuits. Different coupling methods have been proposed between those two types of waveguides without taking into consideration the effect of sandwiching the metal-dielectric-metal (MDM) plasmonic waveguide between the two conventional dielectric waveguides (CDWs). In this research work, using the finite-difference-time-domain method, we numerically analyze the effect of increasing the length of the sandwiched MDM plasmonic waveguide on the extracted light into the output CDW. We found that embedding the MDM plasmonic waveguide between two CDWs causes a reduction in the width of the spectrum response due to the FP cavity-like response compared to that without sandwiching the MDM plasmonic waveguide. We also investigated the effect of changing various parameters of the design dimensions on the spectrum response of our proposed design. Our results indicate potential applications of the proposed design in the integration of ultra-compact nanoplasmonic circuits.