Slot Silicon-Gallium Nitride Waveguide Realizing 1x4 Optical Power Splitter

In this paper, to our knowledge, we introduce the 1x4 optical power splitter operating at 1550nm wavelength for the first time, based on multimode interference (MMI) coupler in slot silicon (Si)-Gallium Nitride (GaN) waveguide structure. Si and GaN were found as suitable materials for slot waveguide structure. Numerical optimizations were carried out on the device parameters using a Full vectorial-beam propagation method (FV-BPM). Simulation results show that the proposed device can be useful to divide optical signal energy uniformly in the C-band range (1530-1565nm) into four output ports with low insertion losses (0.07dB).