A numerical approach to calculate the power transfer between nanoscale waveguides was proposed. Series of complex power-transfer simulations have been performed when comparing two adjacent waveguides made of different materials. The results showed interesting focusing phenomena when coupling a waveguide sharing a high power confinement factor to a waveguide sharing a low one. In addition, we describe the physical properties of a nanoscale integrable waveguide for smooth integration in the microelectronics industry and analyze two case studies regarding such a possible integration. It seems that due to the lack of ability to confine the mode inside a nanoscale dimensions waveguide, combining waveguides with current size transistor may be, at this stage, difficult to realize without specific fits of the whole module.
A Y-junction of low-difference refractive-index (RI) and coupler as its input was designed and simulated. The simulation uses COMSOL Multi-Physics Software Package, allowing varying crucial parameters. A detailed analysis and optimization of the device for single-mode design was made, in order to achieve a maximum input area error while preserving a good 50-50 splitting ratio. This approach of combined design and simulations of special Y-junction can benefit and predict advanced optical communication.