Multimode interferometry for entangling atoms in quantum networks

Barrett, Thomas D., Rubenok, Allison, Stuart, Dustin, Barter, Oliver, Holleczek, Annemarie, Dilley, Jerome, Nisbet-Jones, Peter B. R., Poulios, Konstantinos, Marshall, Graham D., O’Brien, Jeremy L., Politi, Alberto, Matthews, Jonathan C. F. and Kuhn, Axel

Quantum Science and Technology

We bring together a cavity-enhanced light–matter interface with a multimode interferometer (MMI) integrated onto a photonic chip and demonstrate the potential of such hybrid systems to tailor distributed entanglement in a quantum network. The MMI is operated with pairs of narrowband photons produced a priori deterministically from a single 87Rb atom strongly coupled to a high-finesse optical cavity. Non-classical coincidences between photon detection events show no loss of coherence when interfering pairs of these photons through the MMI in comparison to the two-photon visibility directly measured using Hong–Ou–Mandel interference on a beam splitter. This demonstrates the ability of integrated multimode circuits to mediate the entanglement of remote stationary nodes in a quantum network interlinked by photonic qubits.

NQIT Author