Improving the tolerances in high-performance silicon photonics modulators

A racetrack-shaped modulator, based on Double Injection method, has been recently presented able to provide multiple response shapes and exhibiting enhanced robustness to deviations in parameters. Fabrication process deviations that influence sensitive ingredients of ring-based modulators such as the ring’s waveguide, couplers, and heat that is generated in Silicon Photonics devices due to carrier transport, can degrade the modulator extinction-ratio (ER) and optical modulation depth (OMD). The sensitivity of the, so-called, PIR20 configuration (Parameters-Insensitive Response with ER of 20 dB) to fabrication and temperature deviations is analyzed in detail. Comparison to other known modulators based on either a ring, MZI or Fabry-Pérot resonators, reveals that the PIR20 device is considerably less sensitive to deviations of these types.