50 Gb/s Silicon Photonics Receiver With Low Insertion Loss

Optical (de)multiplexers that can provide low insertion loss, low crosstalk, high thermal stability, and insensitivity to fabrication tolerances are essential components for silicon photonics integration. In this letter, we demonstrate the integration of an angled multimode interferometer coarse wavelength division multiplexer with germanium p-i-n photodetectors to form a 50 Gb/s receiver with a low insertion loss of <;-0.5 dB and crosstalk of <;-15 dB. The angled multimode interferometer has the flexibility to be designed on a platform with a wide range of waveguide thicknesses with little variation in performance, which allows for the optimization of other optical components in the photonics integrated circuit.