Device-independent quantum cryptography with input leakage

TL;DR

This paper analyzes device-independent quantum cryptography protocols under input leakage modeled as noise, quantifying how leakage affects randomness certification and secret key rates.

Contribution

It introduces a framework to evaluate the impact of input leakage on device-independent quantum cryptography, relaxing the no-leakage assumption.

Findings

Quantifies local randomness as a function of input leakage.

Determines secret key rates considering input leakage.

Provides bounds on security under noisy input conditions.

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.