Composable end-to-end security of Gaussian quantum networks with untrusted relays

  title={Composable end-to-end security of Gaussian quantum networks with untrusted relays},
  author={Masoud Ghalaii and Panagiotis Papanastasiou and Stefano Pirandola},
  journal={npj Quantum Information},
Gaussian networks are fundamental objects in network information theory. Here many senders and receivers are connected by physically motivated Gaussian channels, while auxiliary Gaussian components, such as Gaussian relays, are entailed. Whilst the theoretical backbone of classical Gaussian networks is well established, the quantum analog is yet immature. Here, we theoretically tackle composable security of arbitrary Gaussian quantum networks, with generally untrusted nodes, in the finite-size… 



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