Phys.org October 10, 2020
Realizing a fully connected network of quantum processors requires the ability to distribute quantum entanglement. For distant processing nodes, this can be achieved by generating, routing, and capturing spatially entangled itinerant photons. Researchers at MIT and MIT Lincoln Laboratory have demonstrated the deterministic generation of such photons using superconducting transmon qubits that are directly coupled to a waveguide. They generated two-photon N00N states and showed that the state and spatial entanglement of the emitted photons are tunable via the qubit frequencies. Using quadrature amplitude detection, they reconstructed the moments and correlations of the photonic modes and demonstrate state preparation fidelities of 84%. The results provide a path toward realizing quantum communication and teleportation protocols using itinerant photons generated by quantum interference within a waveguide quantum electrodynamics architecture…read more. Open Access TECHNICAL ARTICLE
Measurement setup and procedure. Credit: Science Advances 07 Oct 2020: Vol. 6, no. 41, eabb8780