Sequential generation of multiphoton entanglement with a Rydberg superatom

Understand

Multiqubit entanglement is an indispensable resource for quantum information science.

• In particular, the entanglement of photons is of conceptual interest due to its implications in measurement-based quantum computing, communication, and metrology.
• The traditional way of spontaneous parametric down-conversion already demonstrates entanglement of up to a dozen photons but is hindered by its probabilistic nature.
• Here, we experimentally demonstrate an efficient approach for multi-photon generation with a Rydberg superatom, a mesoscopic atomic ensemble under Rydberg blockade.