A Two-Channel Silicon Nitride Multimode Interference Coupler with Low Back Reflection

Optical communication systems based on silicon (Si) multimode interference (MMI) wavelength-division multiplexing (WDM) technology can suffer from back reflection. This undesirable characteristic causes losses and is a key problem that lead to performance limitations. To overcome this limitation, we proposed new study how divide two wavelengths by understanding the light coupling mechanism of nitride (SiN) MMI coupler over C-band window showed four different options design two-channel demultiplexer. The best option for SiN with low reflection operating in spectrum was selected. Based simulation results, device transmit channels spacing 20 nm between C-band. Moreover, has power loss range 0.895–0.936 dB, large bandwidth 16.96–18.77 nm, good crosstalk 23.5–25.86 dB. Usually, unique such as angled required when using Si reduce losses. Due use SiN, which refractive index, obtained 40.4 dB back-reflection without design. Therefore, demultiplexer be used optical WDM technique obtain high data transfer rate conjunction