Multimode Waveguides on an SOI Platform for Arbitrary Power Splitting Ratio Couplers

Abstract

Optical power couplers with arbitrary power splitting ratios are important components for many applications such as Mach-Zehnder interferometer-based structures, filters, switches, dispersion compensations, optical interconnects, and microring resonators. In this chapter, we present a new approach to achieve a very high compact coupler with arbitrary power splitting ratios on silicon on insulator (SOI) waveguides. The proposed device requires only one 4Â4 multimode interference (MMI) coupler. We use a passive wide SOI waveguide to achieve the phase shifter. The footprint of the whole device is only about 6Â150 μm 2. A large fabrication tolerance of AE50 nm can be achieved. The modified effective index method, beam propagation method, finite difference method, and finite difference-time difference method are used to optimally design the whole device.

Design of a 2 × 4 Hybrid MMI-MZI Configuration with MMI Phase-Shifters

“…The results suggested that the total device length should be chosen to be 304 μm to achieve the best operation. These results are comparable and consistent with the results estimated using self-imaging theory [6,24].…”