A micro-processor-based feedback stabilization scheme for high-Q, non-linear silicon resonators

Stabilization of silicon micro-resonators is a key requirement for their inclusion in larger photonic integrated circuits. In particular, thermal refractive index shift in non-linear applications can detune devices from their optimal working point. A cavity stabilization scheme using a micro-processor-based feedback control loop is presented based on a local thermal heater element on-chip. Using this method, a silicon π-phase shifted grating with a cavity Q-factor of 40 k is demonstrated to operate over an ambient temperature detuning range of 40°C and injection wavelength range of 1.5 nm, nearly 3 orders of magnitude greater than the resonant cavity linewidth.