Compact MMI-Based AWGs in a Scalable Monolithic Silicon Photonics Platform

We demonstrate a compact ( $367 \times 67 \, \mu {\text{m}}^2$ ) four-channel wavelength division multiplexer using an arrayed waveguide grating based on multimode interference couplers, and built on a monolithic silicon photonics platform. The design is particularly attractive due to the thin device layer. A semi-numerical approach was used for device design and simulation. Optical measurements were found to be consistent with simulation results. The device channel spacing, 3-dB bandwidth and crosstalk were measured to be 97 GHz, 87 GHz and 9.6 dB, respectively, for the designed wavelength of operation near 1310 nm.