Quantum key distribution based on arbitrarilyweak distillable entangled states (2006).

Content Provider	CiteSeerX
Author	Horodecki, Karol Leung, Debbie
Abstract	We prove unconditional security for a quantum key distribution (QKD) protocol based on distilling pbits (twisted ebits) [1] from an arbitrary untrusted state that is claimed to contain distillable key. Our main result is that we can verify security using only public communication – via parameter estimation of the given untrusted state. The technique applies even to bound entangled states, thus extending QKD to the regime where the available quantum channel has zero quantum capacity. We also show how to convert our purification-based QKD schemes to prepare-measure schemes. I. BACKGROUND, PROBLEM, AND RESULT The most general quantum state (known to the users) which provides a secure key after measurement is not the maximally entangled state (also known as EPR pairs [2] or ebits), but rather, the pbit (sometimes called “twisted ebits”)[1]. Security of entanglement-purification-based Quantum Key Distribution (EPP-QKD) is based on the ability of two separated parties to estimate error rates of an untrusted shared state relative to ebits. Here, we
File Format	PDF
Publisher Date	2006-01-01
Access Restriction	Open
Subject Keyword	Quantum Key Distribution Arbitrarilyweak Distillable Entangled State Entangled State Twisted Ebit Parameter Estimation Entanglement-purification-based Quantum Key Distribution Technique Applies Quantum Capacity Untrusted Shared State Relative Distillable Key Public Communication Separated Party Arbitrary Untrusted State Purification-based Qkd Scheme Secure Key Available Quantum Channel Untrusted State General Quantum State Main Result Unconditional Security Error Rate Prepare-measure Scheme
Content Type	Text