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arXiv · 1410.3443

Quantum randomness protected against detection loophole attacks

Piotr Mironowicz·Gustavo Cañas·Jaime Cariñe·Esteban S. Gómez·Johanna F. Barra·Adán Cabello·Guilherme B. Xavier·Gustavo Lima·Marcin Pawłowski
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Abstract

Device and semi-device independent quantum randomness generators (DI- and SDI-QRNGs) are crucial for applications requiring private randomness. However, they are vulnerable to detection inefficiency attacks and this limits severely their usage for practical purposes. Here, we present a method for protecting SDI-QRNGs in prepare-and-measure scenarios against detection inefficiency attacks. The key idea is the introduction of a blocking device that adds failures in the communication between the preparation and measurement devices. We prove that, for any detection efficiency, there is a blocking rate that provides protection against these attacks. We experimentally demonstrate the generation of private randomness using weak coherent states and standard avalanche photo-detectors.

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Piotr Mironowicz, Gustavo Cañas, Jaime Cariñe, Esteban S. Gómez, Johanna F. Barra, Adán Cabello, Guilherme B. Xavier, Gustavo Lima, Marcin Pawłowski. 2020-11-23. Quantum randomness protected against detection loophole attacks. https://doi.org/10.1007/s11128-020-02948-3

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