{
  "annotation_id": "de255e3d-975f-415c-aca6-51a73e6f9c7a",
  "date_created": "2026-03-02T18:02:03.118000Z",
  "date_modified": "2026-03-02T18:02:03.118000Z",
  "file_hash": "87fbb2e0c0ab1676f6fcd349f16901735bd72f049e1c9fd7f6d426e67174b105",
  "private": false,
  "record": {
    "abstract": "A protocol for quantum secure direct communication using blocks of EPR pairs\nis proposed. A set of ordered $N$ EPR pairs is used as a data block for sending\nsecret message directly. The ordered $N$ EPR set is divided into two particle\nsequences, a checking sequence and a message-coding sequence. After\ntransmitting the checking sequence, the two parties of communication check\neavesdropping by measuring a fraction of particles randomly chosen, with random\nchoice of two sets of measuring bases. After insuring the security of the\nquantum channel, the sender, Alice encodes the secret message directly on the\nmessage-coding sequence and send them to Bob. By combining the checking and\nmessage-coding sequences together, Bob is able to read out the encoded messages\ndirectly. The scheme is secure because an eavesdropper cannot get both\nsequences simultaneously. We also discuss issues in a noisy channel.",
    "arxiv_id": "quant-ph/0308173",
    "authors": [
      "Fu-Guo Deng",
      "Gui Lu Long",
      "Xiao-Shu Liu"
    ],
    "categories": [
      "quant-ph"
    ],
    "doi": "10.1103/PhysRevA.68.042317",
    "journal_ref": "Phys. Rev. A68, 042317 (2003)",
    "title": "A Two-Step Quantum Direct Communication Protocol Using   Einstein-Podolsky-Rosen Pair Block",
    "url": "https://arxiv.org/abs/quant-ph/0308173"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "9569903c-2cb5-402b-8941-4e6ba16e8ac0",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}