{
  "id": "2108.08045",
  "version": "v1",
  "published": "2021-08-18T08:56:02.000Z",
  "updated": "2021-08-18T08:56:02.000Z",
  "title": "Characterizing correlation within multipartite quantum systems via local randomized measurements",
  "authors": [
    "Zhenhuan Liu",
    "Pei Zeng",
    "You Zhou",
    "Mile Gu"
  ],
  "comment": "28 pages, 8 figures. Comments are welcome",
  "categories": [
    "quant-ph"
  ],
  "abstract": "Given a quantum system on many qubits split into a few different parties, how much total correlations are there between these parties? Such a quantity -- aimed to measure the deviation of the global quantum state from an uncorrelated state with the same local statistics -- plays an important role in understanding multi-partite correlations within complex networks of quantum states. Yet, the experimental access of this quantity remains challenging as it tends to be non-linear, and hence often requires tomography which becomes quickly intractable as dimensions of relevant quantum systems scale. Here, we introduce a much more experimentally accessible quantifier of total correlations, which can be estimated using only single-qubit measurements. It requires far fewer measurements than state tomography, and obviates the need to coherently interfere multiple copies of a given state. Thus we provide a tool for proving multi-partite correlations that can be applied to near-term quantum devices.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2021-08-18T08:56:02.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "multipartite quantum systems",
      "local randomized measurements",
      "characterizing correlation",
      "multi-partite correlations",
      "total correlations"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 28,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}