Sparrow Quantum, teaming up with Ruhr University Bochum, has unveiled a deterministic single-photon source that pumps out more than 500 million usable photons per second into a single-mode fiber. According to the company, this marks the highest published single-photon rate to date.

What They Built

The team developed a system that generates single photons on demand and feeds them straight into single-mode optical fiber. The focus here is on “usable” photons—meaning the real-world output, not just what looks good on paper or inside the lab setup.

Tech Specs

Sparrow Quantum says their source runs at a 1 GHz clock rate and achieves over 50% coupling efficiency into the fiber. They’re also touting high single-photon purity and indistinguishability, all without needing any spectral filtering.

What the Company Says

Sparrow Quantum claims this is the highest published single-photon flux so far. Ruhr University Bochum partnered on the project.