{
  "id": "2003.13000",
  "version": "v1",
  "published": "2020-03-29T10:56:15.000Z",
  "updated": "2020-03-29T10:56:15.000Z",
  "title": "Experimental observation of coherent-information superadditivity in a dephrasure channel",
  "authors": [
    "Yu Shang",
    "Yu Meng",
    "Raj B. Patel",
    "Yi-Tao Wang",
    "Zhi-Jin Ke",
    "Wei Liu",
    "Zhi-Peng Li",
    "Yuan-Ze Yang",
    "Wen-Hao Zhang",
    "Jian-Shun Tang",
    "Chuan-Feng Li",
    "Guang-Can Guo"
  ],
  "categories": [
    "quant-ph"
  ],
  "abstract": "We present an experimental approach to construct a dephrasure channel, which contains both dephasing and erasure noises, and can be used as an efficient tool to study the superadditivity of coherent information. By using a three-fold dephrasure channel, the superadditivity of coherent information is observed, and a substantial gap is found between the zero single-letter coherent information and zero quantum capacity. Particularly, we find that when the coherent information of n channel uses is zero, in the case of larger number of channel uses, it will become positive. These phenomena exhibit a more obvious superadditivity of coherent information than previous works, and demonstrate a higher threshold for non-zero quantum capacity. Such novel channels built in our experiment also can provide a useful platform to study the non-additive properties of coherent information and quantum channel capacity.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-03-29T10:56:15.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "experimental observation",
      "coherent-information superadditivity",
      "zero single-letter coherent information",
      "novel channels built",
      "non-zero quantum capacity"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}