{
  "id": "2302.01322",
  "version": "v1",
  "published": "2023-02-02T18:50:42.000Z",
  "updated": "2023-02-02T18:50:42.000Z",
  "title": "Universality in the tripartite information after global quenches: (generalised) quantum XY models",
  "authors": [
    "Vanja Marić",
    "Maurizio Fagotti"
  ],
  "categories": [
    "cond-mat.stat-mech",
    "hep-th",
    "quant-ph"
  ],
  "abstract": "We consider the R\\'enyi-$\\alpha$ tripartite information $I_3^{(\\alpha)}$ of three adjacent subsystems in the stationary state emerging after global quenches in noninteracting spin chains from both homogeneous and bipartite states. We identify settings in which $I_3^{(\\alpha)}$ remains nonzero also in the limit of infinite lengths and develop a field theory description. We map the calculation into a Riemann-Hilbert problem with a piecewise constant matrix for a doubly connected domain. We find an explicit solution for $\\alpha=2$ and an implicit one for $\\alpha>2$. In the latter case, we develop a rapidly convergent perturbation theory that we use to derive analytic formulae approximating $I_3^{(\\alpha)}$ with outstanding accuracy.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2023-02-02T18:50:42.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "quantum xy models",
      "global quenches",
      "tripartite information",
      "universality",
      "rapidly convergent perturbation theory"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}