Multimode Interference Power-Splitter Using InP-Based Deeply Etched Hybrid Plasmonic Waveguide

The present study proposes a novel nanoscale multimode interference (MMI) power splitter utilizing an InP-based hybrid plasmonic waveguide at an optical communication wavelength. The layer stack has the potential to realize monolithic integrated hybrid plasmonic passive and active components. The 1 × 2, 1 × 3, and 2 × 2 MMI power splitters were simulated and optimized using a three-dimensional finite difference time domain method. The effect of MMI length, width, and wavelength on optical power transmission was investigated. Transmission was higher than 90% at 1.55 μm wavelengths. This study also presents an ultracompact shallow to deep transition between shallow-etched conventional waveguide and a hybrid plasmonic waveguide on an InP-substrate. It was shown that shallow to deep transition with a length of 2 μm has a coupling efficiency of 87.5%.