{
  "id": "1702.05396",
  "version": "v1",
  "published": "2017-02-17T15:39:16.000Z",
  "updated": "2017-02-17T15:39:16.000Z",
  "title": "Complex semiclassical analysis of the Loschmidt amplitude and dynamical quantum phase transitions",
  "authors": [
    "Tomoyuki Obuchi",
    "Sei Suzuki",
    "Kazutaka Takahashi"
  ],
  "comment": "12 pages, 11 figures",
  "categories": [
    "cond-mat.stat-mech",
    "quant-ph"
  ],
  "abstract": "We propose a new computational method of the Loschmidt amplitude in a generic spin system on the basis of the complex semiclassical analysis on the spin-coherent state path integral. We demonstrate how the dynamical transitions emerge in the time evolution of the Loschmidt amplitude for the infinite-range transverse Ising model with a longitudinal field, exposed by a quantum quench of the transverse field $\\Gamma$ from $\\infty$ or $0$. For both initial conditions, we obtain the dynamical phase diagrams that show the presence or absence of the dynamical transition in the plane of transverse field after a quantum quench and the longitudinal field. The results of semiclassical analysis are verified by numerical experiments. Experimental observation of our findings on the dynamical transition is also discussed.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-02-17T15:39:16.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "dynamical quantum phase transitions",
      "complex semiclassical analysis",
      "loschmidt amplitude",
      "dynamical transition",
      "quantum quench"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 12,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}