



01264nas a2200157   4500008004100000245006300041210006300104520077600167100002100943700002100964700002000985700002001005700002001025700002401045856003701069       2018                        eng d00aHigh Purity Single Photons Entangled with an Atomic Memory0 aHigh Purity Single Photons Entangled with an Atomic Memory3 a<p>Trapped atomic ions are an ideal candidate for quantum network nodes, with long-lived identical qubit memories that can be locally entangled through their Coulomb interaction and remotely entangled through photonic channels. The integrity of this photonic interface is generally reliant on purity of single photons produced by the quantum memory. Here we demonstrate a single-photon source for quantum networking based on a trapped 138Ba+ ion with a single photon purity of g2(0)=(8.1&plusmn;2.3)&times;10&minus;5 without background subtraction. We further optimize the tradeoff between the photonic generation rate and the memory-photon entanglement fidelity for the case of polarization photonic qubits by tailoring the spatial mode of the collected light.&nbsp;</p>1 aCrocker, Clayton1 aLichtman, Martin1 aSosnova, Ksenia1 aCarter, Allison1 aScarano, Sophia1 aMonroe, Christopher  uhttps://arxiv.org/abs/1812.01749