Sparrow Quantum has collaborated with Ruhr University Bochum to create a deterministic source that produces over 500 million usable photons per second in a single-mode fiber. This achievement was reported by The Quantum Insider citing the company's press release.
According to Sparrow Quantum, the system operates at a frequency of 1 GHz and achieves an input efficiency into the fiber exceeding 50%. The company also highlighted the high purity of the single photons and their indistinguishability without spectral filtering. Sparrow Quantum claims this result represents the highest published flow of single photons to date.
The flow exceeds 100 pW of optical power, which can be measured using a standard optical power meter. The company believes this development will be beneficial for metrology, serving as a standard for photon flow and a tool for calibrating single photon detectors.
After being split into 10 channels through space-time demultiplexing, the source reportedly delivers tens of millions of photons per second per channel. Sparrow Quantum asserts that this is sufficient for practical experiments involving 10 photons and interference of approximately 10–20 particles. The company lists potential applications in quantum computing, networking, communications, and metrology.
Juan Carlos Loredo, Vice President of Innovation at Sparrow Quantum, stated that this new flow rate alleviates some limitations on multiphoton experiments. The company's founder, Peter Lodahl, identified scalable generation and control of entanglement in larger photonic quantum systems as the next significant challenge.
It is worth noting that in August, an international team of scientists achieved quantum entanglement using sunlight.