Quantum cryptography based on qutrit Bell inequalities

Multidimensional Bell Inequalities and Quantum Cryptography

A qutrit Quantum Key Distribution protocol using Bell inequalities with larger violation capabilities

The Ekert quantum key distribution protocol [1] uses pairs of entangled qubits and performs checks based on a Bell inequality to detect eavesdropping. The 3DEB protocol [2] uses instead pairs of entangled qutrits to achieve better noise resistance than the Ekert protocol. It performs checks based on a Bell inequality for qutrits named CHSH-3 and found in [3, 4]. In this paper, we present a new ...

Comment on " Bell Inequalities and Quantum Mechanics "

Errors in Eberly’s derivation of several Bell inequalities are pointed out: (1) it is based on an equation that is incorrect; (2) it uses neither two-particle states nor locality to derive Bell’s inequalities and; (3) it does not use entanglement to obtain violations of Bell’s inequalities. Even leading and outstanding physicists – as certainly is the case of Prof. Eberly – sometimes make eleme...

A practical trojan horse for bell-inequality-based quantum cryptography

Quantum Cryptography, or more accurately, Quantum Key Distribution (QKD) is based on using an unconditionally secure “quantum channel” to share a secret key among two users. A manufacturer of QKD devices could, intentionally or not, use a (semi-)classical channel instead of the quantum channel, which would remove the supposedly unconditional security. One example is the BB84 protocol, where the...

Nonlinear Bell Inequalities Tailored for Quantum Networks.

In a quantum network, distant observers sharing physical resources emitted by independent sources can establish strong correlations, which defy any classical explanation in terms of local variables. We discuss the characterization of nonlocal correlations in such a situation, when compared to those that can be generated in networks distributing independent local variables. We present an iterati...