8CH AWG Multi/Demultiplexer With MEMS Variable Optical Attenuator

An integrated arrayed waveguide grating multi/demultiplexer (AWG) with a micro-electro-mechanical systems (MEMS) based variable optical attenuator (VOA) is reported. The device consists of an AWG based on silica and a MEMS-VOA chip. The MEMS chip includes 100 μm × 100 μm polysilicon shutter plates coated with gold and electrostatic comb-drive actuators. The MEMS chip is interposed in a trench located in the middle of the I/O waveguides of the AWG to tune the optical transmitting power intensity through the waveguides continuously. The MEMS-VOA shutters have more than a 10 μm displacement. Using those shutters, 30 dB optical contrast from 5 dB at the transmit state to 35 dB at the isolation state is achieved. The obtained attenuation contrast is greater than that of a conventional waveguide-based Mach-Zehnder interferometer VOA and sufficient to adjust and equalize the optical signal power in the wavelength division multiplexing (WDM) network systems.