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arXiv · 0908.2735

Tight bound on coherent-state-based entanglement generation over lossy channels

Koji Azuma·Naoya Sota·Masato Koashi·Nobuyuki Imoto
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Abstract

The first stage of the hybrid quantum repeaters is entanglement generation based on transmission of pulses in coherent states over a lossy channel. Protocols to make entanglement with only one type of error are favorable for rendering subsequent entanglement distillation efficient. Here we provide the tight upper bound on performances of these protocols that is determined only by the channel loss. In addition, we show that this bound is achievable by utilizing a proposed protocol [arXiv:0811.3100] composed of a simple combination of linear optical elements and photon-number-resolving detectors.

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Koji Azuma, Naoya Sota, Masato Koashi, Nobuyuki Imoto. 2009-08-19. Tight bound on coherent-state-based entanglement generation over lossy channels. https://doi.org/10.1103/physreva.81.022325

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