Design and analysis of a novel triangular nano plasmonic coupler with an enhanced coupling efficiency

Abstract

Plasmonics has sparked a lot of interest in nanophotonics research. By managing optical communication systems based on photonic circuits and optical fibers, plasmonics helps to improve the performance of conventional electric circuits in digital communication. Nonetheless, the integration of photonics into electronic circuits, which are currently on the nanoscale scale, has been hampered by photonics micrometer-scale components. Researchers are now interested in the ability of plasmonics-based devices to overcome the diffraction limit often encountered in subwavelength devices. As the demand for plasmonics-based devices has grown, so has the need for a plasmonic coupler to make these plasmonic-based devices compatible with existing non plasmonic devices. In this thesis, a theoretical three-dimensional study of the effective coupling of light between a metal-insulator-metal (MIM) type plasmonic waveguide and a dielectric waveguide has been conducted. This thesis presents a unique triangular, three-dimensional nano plasmonic coupler design and analysis. This triangular nano plasmonic coupler couples a Silicon waveguide and metal-insulator-metal (MIM) waveguide. Coupling efficiency is an important metric for assessing the performance of nanoplasmonic couplers. With a view to attaining better efficiency, a novel structure has been proposed in this thesis which yields a better transmission efficiency to a wide range of wavelengths with the highest being at 95.3%. Optimum dimensions of the triangular coupler have been attained based on systematic adjustments in the structural parameters to maximize the coupling efficiency. It can be stated that the proposed coupler in this thesis has a higher coupling efficiency than a number of standard couplers currently available. It is envisaged that the proposed structure and analysis can pave the way for a more effective nanoplasmonic coupler design. We believe that our proposed design will contribute significantly to the advancement of functional nanoplasmonic couplers