A tunable photonic temporal integrator with ultra-long integration time windows based on Raman-gain assisted phase-shifted silicon Bragg gratings

A tunable photonic temporal integrator based on Raman-gain assisted phase-shifted silicon Bragg gratings is proposed and theoretically demonstrated. The proposed temporal photonic integrator is constructed using a silicon-on-insulator (SOI) π-phase-shifted Bragg grating, with a 25 V reverse bias applied to the p–i–n rib waveguide. Key feature of our design is that the length of integration time window could be widely tuned by simply changing the optical power of the pump light and could be extended to very long when the pump power is approaching lasing threshold. In addition, this scheme also has the potential for on-chip integration with other silicon photonics components.