Designing Quantum Networks: From QKD links to the Quantum Internet

It is now widely accepted that quantum mechanics and its associated technologies allow one to perform tasks that have been considered unthinkable from the classical world. Many of these technologies will be naturally distributed and will require quantum networks to connect them together. It will be essential that high fidelity entangled pairs can be generated between these distributed sites in an efficient manner. Quantum repeaters are often considered to be the main means to achieve this goal, but they are facing numerous technological challenges. One must design such systems to not only have excellent performance but to be also resource efficient. In this presentation we will begin by discussing the various approaches to quantum repeaters and show how memory assisted mdiQKD provides a natural bridge to entanglement based quantum networks.  We will present a scheme based on a quantum photonic multiplexer combining entanglement distribution and purification into a single step operation resulting in high fidelity Bell pairs with improved generation rates using fewer physical resources. Our approach should improve the performance of quantum communication systems and repeater networks.