Entanglement of two quantum bits is equivalent to secure key distribution

Preprint

10 March 2003

preprint
Published by arXiv in arXiv

Abstract

We study the problem of secret key distillation from two-qubit states in the scenario where Alice and Bob can only perform measurements at the single-copy level and classically process the obtained outcomes. Therefore, no quantum distillation technique, i.e. joint operation on several copies of the local state, is allowed. We prove that, even with these limitations, secret bits can be asymptotically distilled by the honest parties from any entangled state. This result implies a complete equivalence between two-qubit entanglement and secure key distribution: a key can be safely established through a one-qubit channel if and only if it allows to distribute entanglement.

Keywords

SECURE KEY DISTRIBUTION
QUANTUM BITS
DISTILLATION
ENTANGLEMENT
TWO QUANTUM
TWO QUBIT

All Related Versions

Version 1, 2003-03-10, ArXiv
Version 2, 2003-04-01, ArXiv
Version 3, 2003-09-23, ArXiv
Published version: Physical Review Letters, 91 (16), 167901.

This publication has 0 references indexed in Scilit: