Device Independent Quantum Key Activation

Abstract

Device-independent quantum key distribution (DIQKD) allows two distant parties to establish a secret key, based only on the observed Bell nonlocal distribution. It remains however, unclear what the minimal resources for enabling DIQKD are and how to maximize the key rate from a given distribution. In the present work, we consider a scenario where several copies of a given quantum distribution are jointly processed via a local and classical wiring operation. We find that, under few assumptions, it is possible to activate device-independent key. That is, starting from a distribution that is useless in a DIQKD protocol, we obtain a positive key rate by wiring several copies together. We coin this effect device-independent key activation. Our analysis focuses on the standard DIQKD protocol with one-way post-processing, and we resort to semi-definite programming techniques for computing lower bounds on the key rate.

References in corpus (26)

• Device-independent security of quantum cryptography against collective attacks
• Random Numbers Certified by Bell's Theorem
• No Signalling and Quantum Key Distribution
• Distillation of secret key and entanglement from quantum states
• A convergent hierarchy of semidefinite programs characterizing the set of quantum correlations
• From Bell's Theorem to Secure Quantum Key Distribution
• Device-independent quantum key distribution secure against collective attacks
• Advances in device-independent quantum key distribution
• Simple and tight device-independent security proofs
• Entropy accumulation
• Efficient quantum key distribution secure against no-signalling eavesdroppers
• Non-locality distillation and post-quantum theories with trivial communication complexity
• Distilling Non-Locality
• Algorithm 950: Ncpol2sdpa---Sparse Semidefinite Programming Relaxations for Polynomial Optimization Problems of Noncommuting Variables
• Closed sets of non-local correlations
• Noisy pre-processing facilitating a photonic realisation of device-independent quantum key distribution
• Bell nonlocality is not sufficient for the security of standard device-independent quantum key distribution protocols
• Computing secure key rates for quantum key distribution with untrusted devices
• Device-independent lower bounds on the conditional von Neumann entropy
• Monotone Measures for Non-Local Correlations
• Device-independent quantum key distribution with arbitrarily small nonlocality
• Advantages of multi-copy nonlocality distillation and its application to minimizing communication complexity
• Distilling Nonlocality in Quantum Correlations
• Nonlocality Distillation and Quantum Voids
• Upper bounds on key rates in device-independent quantum key distribution based on convex-combination attacks
• Multi-system measurements in generalized probabilistic theories and their role in information processing