Performance Analysis of Multiple Strips to Reduce the Separation of Photonic Waveguides in Photonic Array

In order to construct a dense Photonic Integrated Circuit (PIC) that comprises photonic waveguides, it is vital to consider the necessity of low crosstalk between surrounding waveguides. From past literature, higher coupling length can be obtained by utilizing a silicon – on -insulator (SOI) based photonic waveguide with an acceptable waveguide separation between them. The current research aims to reduce waveguide separation and hence increase photonic integration over PICs. Numerous strips were inserted between the photonic waveguides to achieve this. The impact of modifications in height and width of three, four, and five strips on coupling has been analyzed. This has led to the inference that larger coupling lengths can be achieved. The greatest coupling lengths of 485 µm, 620 µm, and 104110 µm were reached with end-to-end waveguide separations between the two adjacent waveguides of 175 nm for three strips, four strips and five strips inserted between two photonic waveguides. Achieving a coupling length of 104110 µm proves that the proposed design is better than previously proposed designs in terms of coupling length. In addition, we have compared the coupling lengths obtained when Ge strips and Si strips were inserted between the photonic waveguides. The method given in this paper can be used to design a variety of photonic applications.