Jörg Duhme

Providing estimations and numerical approximations for expected rates of entanglement generation in quantum repeater protocols has been the focus of a lot of research to date. We contribute to this work by providing a set of analytical results for a large class of possible models, with respect to generalized anti-bunched photon emissions statistics of qubit sources. These allow us on the one hand to verify existing estimations and on the other hand to construct new lower bound estimations for the time-resolved execution of quantum repeater processes.

The QKD-setup under consideration is comprised of two initially independent squeezed continuous Gaussian states (squeezing 11 dB, anti-squeezing 16 dB) at 1550 nm which become entangled by a 50:50 beam splitter. F. Furrer et al presented a security analysis for the setting we explained above assuming collective and coherent attacks [PRL 109, 100502 (2012)]. We will especially discuss the subtleties of the key generation and propose a new error correction algorithm allowing for the generation of a coherent-attack-secure key in experiment.