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arXiv · 1105.2573

Heralded qubit amplifiers for practical device-independent quantum key distribution

Marcos Curty·Tobias Moroder
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Abstract

Device-independent quantum key distribution does not need a precise quantum mechanical model of employed devices to guarantee security. Despite of its beauty, it is still a very challenging experimental task. We compare a recent proposal by Gisin et al. [Phys. Rev. Lett. 105, 070501 (2010)] to close the detection loophole problem with that of a simpler quantum relay based on entanglement swapping with linear optics. Our full-mode analysis for both schemes confirms that, in contrast to recent beliefs, the second scheme can indeed provide a positive key rate which is even considerably higher than that of the first alternative. The resulting key rates and required detection efficiencies of approx. 95% for both schemes, however, strongly depend on the underlying security proof.

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Marcos Curty, Tobias Moroder. 2011-05-12. Heralded qubit amplifiers for practical device-independent quantum key distribution. https://doi.org/10.1103/physreva.84.010304

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