Graduate student Huaixiu Zheng recently published a paper in PRL titled “Persistent Quantum Beats and Long-Distance Entanglement from Waveguide-Mediated Interactions,” together with his advisor Prof. Harold Baranger. This is their second paper in PRL on the topic of waveguide-QED, which explores the interaction between local quantum objects---qubits---and light confined in a one-dimensional waveguide. The key question addressed is how two distant qubits talk to each other via a common waveguide-bus. Zheng developed a novel numerical Green function method, which for the first time enables access to the non-Markovian regime in 1D waveguide-QED systems (where one has to take into account memory effects in the waveguide). Surprisingly, even when the two qubits are far apart, they are strongly entangled and can generate strongly-correlated photons inside the waveguide. This originates from the special 1D nature of the waveguide. The long-distance entanglement demonstrated in this work makes 1D waveguide-QED systems promising candidates for scalable quantum networking. For details, you can read the PRL article online here.