dorsal/arxiv
View SchemaStructured Codes Improve the Bennett-Brassard-84 Quantum Key Rate
| Authors | Graeme Smith, Joseph M. Renes, John A. Smolin |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0607018 |
| URL | https://arxiv.org/abs/quant-ph/0607018 |
| DOI | 10.1103/PhysRevLett.100.170502 |
| Journal | Phys. Rev. Lett. 100, 170502 (2008) |
Abstract
A central goal in information theory and cryptography is finding simple characterizations of optimal communication rates subject to various restrictions and security requirements. Ideally, the optimal key rate for a quantum key distribution (QKD) protocol would be given by {\em single-letter formula} involving a simple optimization over a single use of an effective channel. We explore the possibility of such a formula for one of the simplest and most widely used QKD protocols--Bennett-Brassard-84 (BB84) with one way classical post-processing. We show that a conjectured single-letter key-rate formula is false, uncovering a deep ignorance about asymptotically good private codes and pointing towards unfortunate complications in the theory of QKD. These complications are not without benefit--with added complexity comes better key rates than previously thought possible. We improve the threshold for secure key generation from a bit error rate of 0.124 to 0.129.
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"abstract": "A central goal in information theory and cryptography is finding simple\ncharacterizations of optimal communication rates subject to various\nrestrictions and security requirements. Ideally, the optimal key rate for a\nquantum key distribution (QKD) protocol would be given by {\\em single-letter\nformula} involving a simple optimization over a single use of an effective\nchannel. We explore the possibility of such a formula for one of the simplest\nand most widely used QKD protocols--Bennett-Brassard-84 (BB84) with one way\nclassical post-processing. We show that a conjectured single-letter key-rate\nformula is false, uncovering a deep ignorance about asymptotically good private\ncodes and pointing towards unfortunate complications in the theory of QKD.\nThese complications are not without benefit--with added complexity comes better\nkey rates than previously thought possible. We improve the threshold for secure\nkey generation from a bit error rate of 0.124 to 0.129.",
"arxiv_id": "quant-ph/0607018",
"authors": [
"Graeme Smith",
"Joseph M. Renes",
"John A. Smolin"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevLett.100.170502",
"journal_ref": "Phys. Rev. Lett. 100, 170502 (2008)",
"title": "Structured Codes Improve the Bennett-Brassard-84 Quantum Key Rate",
"url": "https://arxiv.org/abs/quant-ph/0607018"
},
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