Scalable multiphoton generation from cavity-synchronized single-photon sources

We propose an efficient, scalable and deterministic scheme to generate up to hundreds of indistinguishable photons over multiple channels, on demand. Our design relies on multiple single-photon sources, each coupled to a waveguide, and all of them interacting with a common cavity mode. The cavity synchronizes and triggers the simultaneous emission of one photon by each source, which are collected by the waveguides. For a state-of-the-art circuit QED implementation, this scheme supports the creation of single photons with purity, indistinguishability, and efficiency of 99% at rates of ∼MHz. We also discuss conditions to create a device to produce 30-photon simultaneously with efficiency above 70% at a rate of hundreds of kHz. This is several orders of magnitude more efficient than previous demultiplexed sources for boson sampling, and enables the realization of deterministic multi-photon sources and scalable quantum information processing with photons. [See arXiv:2009.02382]