A compact design of a balanced $1\times 4$ optical power splitter based on silicon on insulator slot waveguides

In this paper, a compact design of a balanced $1 \times 4$ optical power splitter based on coupled mode theory (CMT) is presented. The design consists of seven vertically slotted waveguides based on the silicon-on-insulator platform. The $1 \times 4$ OPS is modelled using commercial finite element method (FEM) simulation tool COMSOL Multiphysics 5.1. The optimized OPS is capable of working across the whole C-band with maximum $\sim 39 \%$ of power decay in the wavelength range 1530-1565 nm.