dorsal/arxiv
View Schema"Squashed Entanglement" - An Additive Entanglement Measure
| Authors | Matthias Christandl, Andreas Winter |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0308088 |
| URL | https://arxiv.org/abs/quant-ph/0308088 |
| DOI | 10.1063/1.1643788 |
| Journal | J. Math. Phys. Vol 45, No 3, pp. 829-840 (2004) |
Abstract
In this paper, we present a new entanglement monotone for bipartite quantum states. Its definition is inspired by the so-called intrinsic information of classical cryptography and is given by the halved minimum quantum conditional mutual information over all tripartite state extensions. We derive certain properties of the new measure which we call "squashed entanglement": it is a lower bound on entanglement of formation and an upper bound on distillable entanglement. Furthermore, it is convex, additive on tensor products, and superadditive in general. Continuity in the state is the only property of our entanglement measure which we cannot provide a proof for. We present some evidence, however, that our quantity has this property, the strongest indication being a conjectured Fannes type inequality for the conditional von Neumann entropy. This inequality is proved in the classical case.
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"abstract": "In this paper, we present a new entanglement monotone for bipartite quantum\nstates. Its definition is inspired by the so-called intrinsic information of\nclassical cryptography and is given by the halved minimum quantum conditional\nmutual information over all tripartite state extensions. We derive certain\nproperties of the new measure which we call \"squashed entanglement\": it is a\nlower bound on entanglement of formation and an upper bound on distillable\nentanglement. Furthermore, it is convex, additive on tensor products, and\nsuperadditive in general.\n Continuity in the state is the only property of our entanglement measure\nwhich we cannot provide a proof for. We present some evidence, however, that\nour quantity has this property, the strongest indication being a conjectured\nFannes type inequality for the conditional von Neumann entropy. This inequality\nis proved in the classical case.",
"arxiv_id": "quant-ph/0308088",
"authors": [
"Matthias Christandl",
"Andreas Winter"
],
"categories": [
"quant-ph"
],
"doi": "10.1063/1.1643788",
"journal_ref": "J. Math. Phys. Vol 45, No 3, pp. 829-840 (2004)",
"title": "\"Squashed Entanglement\" - An Additive Entanglement Measure",
"url": "https://arxiv.org/abs/quant-ph/0308088"
},
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