Analysis and design plasmonic directional coupler using hybrid plasmonic waveguide

One of the most important plasmonic structures is the plasmonic directional coupler, which is a variety of applications such as switches, multiplexers, splitters, power dividers and mixers, polarization dividers, modulators, and frequency selector filters. In this paper was introduced important parameters in a directional coupler, and the latest research has been done to improve these parameters for integrated optical circuit applications. Further, the coupler structure is proposed which has better parameters than other structures for integrated optical circuit. By analyzing the results, it can be seen that the proposed coupler has a maximum coupling coefficient of 90% and isolation coefficient of 19 dB, which is good value compared to other proposed structures. Its structure is simpler than the other glued structure, so making it easier. Also, due to the presence of two layers of metal on both sides of this structure, interference with other tools is prevented. The dimensions of this coupler are about 1 μm, which is a very compact structure and suitable for use in integrated optical circuits.