Device-independent quantum cryptography with input leakage

Víctor Zapatero; Marcos Curty

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arXiv · 2604.20573

Device-independent quantum cryptography with input leakage

Víctor Zapatero·Marcos Curty

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Abstract

Device-independence is the gold standard of quantum cryptography. To meet this standard, a central assumption is that no information leakage occurs during protocol execution. We relax this assumption by analyzing CHSH-based randomness certification and key distribution with partial leakage of the inputs, modeled in terms of a noisy channel. Our results quantify the certifiable local randomness and the secret key rate as a function of the magnitude of the input leakage.

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Víctor Zapatero, Marcos Curty. 2026-04-22. Device-independent quantum cryptography with input leakage. https://arxiv.org/abs/2604.20573

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