Numerical investigation on cascaded 1 × 3 photonic crystal power splitter based on asymmetric and symmetric 1 × 2 photonic crystal splitters designed with flexible structural defects.

We propose a photonic crystal slab-based 1 × 3 power splitter with high output transmission and equal power distribution. It is designed by cascading an asymmetric 1 × 2 power splitter and a symmetric 1 × 2 power splitter. Desired equal power splitting is achieved by introducing and optimizing the splitting region of the 1 × 2 power splitters with flexible structural defects. Simulations were carried out by using 3-D Finite Difference Time Domain method showing equal normalized power distributions of 29.6%, 28.9% and 30.5% at 1550 nm optical wavelength. In addition, equal power splitting also takes place at 1561 nm.