Quantum information processing is set to play a large role in future communication technology. Promising realizations for long-distance quantum communication are based on photons. Due to the prospect of moving them out of the lab and toward scalable real-world applications, photonic integrated circuits (PICs) have attracted significant attention. Mature foundry-based PIC platforms based on silicon and silicon nitride have the potential to be a stepping-stone in this development. Especially for necessary switching and routing of single photons including nanosecond delay lines, achieving ultralow losses is key and switching bandwidths should match the single-photon generation rate, which is typically in the MHz to GHz regime for quantum-dot based sources. All-optical switches based on silicon nitride microring resonators are evaluated for their integration with gigahertz single-photon sources. Requirements for the resonator characteristics and control signal waveform are obtained from the Kerr nonlinear dynamics and travelling-wave simulations, and demonstrate the feasibility for single-photon switching in a mature foundry-based PIC platform.
