dorsal/arxiv
View SchemaThe quantum capacity with symmetric side channels
| Authors | Graeme Smith, John A. Smolin, Andreas Winter |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0607039 |
| URL | https://arxiv.org/abs/quant-ph/0607039 |
| DOI | 10.1109/TIT.2008.928269 |
| Journal | IEEE Trans. Info. Theory 54, 9, 4208-4217 (2008) |
| License | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ |
Abstract
We present an upper bound for the quantum channel capacity that is both additive and convex. Our bound can be interpreted as the capacity of a channel for high-fidelity quantum communication when assisted by a family of channels that have no capacity on their own. This family of assistance channels, which we call symmetric side channels, consists of all channels mapping symmetrically to their output and environment. The bound seems to be quite tight, and for degradable quantum channels it coincides with the unassisted channel capacity. Using this symmetric side channel capacity, we find new upper bounds on the capacity of the depolarizing channel. We also briefly indicate an analogous notion for distilling entanglement using the same class of (one-way) channels, yielding one of the few entanglement measures that is monotonic under local operations with one-way classical communication (1-LOCC), but not under the more general class of local operations with classical communication (LOCC).
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"abstract": "We present an upper bound for the quantum channel capacity that is both\nadditive and convex. Our bound can be interpreted as the capacity of a channel\nfor high-fidelity quantum communication when assisted by a family of channels\nthat have no capacity on their own. This family of assistance channels, which\nwe call symmetric side channels, consists of all channels mapping symmetrically\nto their output and environment. The bound seems to be quite tight, and for\ndegradable quantum channels it coincides with the unassisted channel capacity.\nUsing this symmetric side channel capacity, we find new upper bounds on the\ncapacity of the depolarizing channel. We also briefly indicate an analogous\nnotion for distilling entanglement using the same class of (one-way) channels,\nyielding one of the few entanglement measures that is monotonic under local\noperations with one-way classical communication (1-LOCC), but not under the\nmore general class of local operations with classical communication (LOCC).",
"arxiv_id": "quant-ph/0607039",
"authors": [
"Graeme Smith",
"John A. Smolin",
"Andreas Winter"
],
"categories": [
"quant-ph"
],
"doi": "10.1109/TIT.2008.928269",
"journal_ref": "IEEE Trans. Info. Theory 54, 9, 4208-4217 (2008)",
"license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
"title": "The quantum capacity with symmetric side channels",
"url": "https://arxiv.org/abs/quant-ph/0607039"
},
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