{
  "id": "2008.03083",
  "version": "v1",
  "published": "2020-08-07T10:50:35.000Z",
  "updated": "2020-08-07T10:50:35.000Z",
  "title": "Equivalence of space and time-bins in DPS-QKD",
  "authors": [
    "Gautam Shaw",
    "Shyam Sridharan",
    "Shashank Ranu",
    "Foram Shingala",
    "Prabha Mandayam",
    "Anil Prabhakar"
  ],
  "comment": "7 pages, 14 figures",
  "categories": [
    "quant-ph"
  ],
  "abstract": "We set up differential phase shift quantum key distribution (DPS-QKD), over 105 km of single-mode optical fiber, with a quantum bit error rate of less than 15% at a secure key rate of 2 kbps. The testbed was first used to investigate the effect of excess bias voltage and hold-off time on the temporal distribution of photons within a gate window of an InGaAs single-photon detector (SPD) and quantified the effects of afterpulsing. The key generation efficiency, and security, in DPS-QKDimprove with an increase in the number of path delays or time-bin superpositions. We finally demonstrate the implementation of superposition states using a time-bin approach, and establish equivalence with the path-based superposition approach, thus yielding a simpler approach to implementing superposition states for use in DPS-QKD.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-08-07T10:50:35.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "equivalence",
      "differential phase shift quantum",
      "quantum bit error rate",
      "ingaas single-photon detector",
      "excess bias voltage"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 7,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}