arXiv:1903.10535 · Physical Review Letters

Advantage Distillation for Device-Independent Quantum Key Distribution

Ernest Y.-Z. Tan, Charles Ci Wen Lim, Renato Renner

Published Jan 16, 2020• 69 citations

Abstract

Device-independent quantum key distribution (DIQKD) offers the prospect of distributing secret keys with only minimal security assumptions, by making use of a Bell violation. However, existing DIQKD security proofs have low noise tolerances, making a proof-of-principle demonstration currently infeasible. We investigate whether the noise tolerance can be improved by using advantage distillation, which refers to using two-way communication instead of the one-way error correction currently used in DIQKD security proofs. We derive an efficiently verifiable condition to certify that advantage distillation is secure against collective attacks in a variety of DIQKD scenarios, and use this to show that it can indeed allow higher noise tolerances, which could help to pave the way towards an experimental implementation of DIQKD.

DOI: 10.1103/physrevlett.124.020502

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