dorsal/arxiv
View SchemaQubit channels that achieve capacity with two states
| Authors | Dominic W. Berry |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0412113 |
| URL | https://arxiv.org/abs/quant-ph/0412113 |
| DOI | 10.1103/PhysRevA.71.032334 |
| Journal | Phys. Rev. A 71, 032334 (2005). |
Abstract
This paper considers a class of qubit channels for which three states are always sufficient to achieve the Holevo capacity. For these channels it is known that there are cases where two orthogonal states are sufficient, two non-orthogonal states are required, or three states are necessary. Here a systematic theory is given which provides criteria to distinguish cases where two states are sufficient, and determine whether these two states should be orthogonal or non-orthogonal. In addition, we prove a theorem on the form of the optimal ensemble when three states are required, and present efficient methods of calculating the Holevo capacity.
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"abstract": "This paper considers a class of qubit channels for which three states are\nalways sufficient to achieve the Holevo capacity. For these channels it is\nknown that there are cases where two orthogonal states are sufficient, two\nnon-orthogonal states are required, or three states are necessary. Here a\nsystematic theory is given which provides criteria to distinguish cases where\ntwo states are sufficient, and determine whether these two states should be\northogonal or non-orthogonal. In addition, we prove a theorem on the form of\nthe optimal ensemble when three states are required, and present efficient\nmethods of calculating the Holevo capacity.",
"arxiv_id": "quant-ph/0412113",
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"Dominic W. Berry"
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"doi": "10.1103/PhysRevA.71.032334",
"journal_ref": "Phys. Rev. A 71, 032334 (2005).",
"title": "Qubit channels that achieve capacity with two states",
"url": "https://arxiv.org/abs/quant-ph/0412113"
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