{
  "id": "0705.3566",
  "version": "v1",
  "published": "2007-05-24T12:03:49.000Z",
  "updated": "2007-05-24T12:03:49.000Z",
  "title": "Experimental Observation of a Topological Phase in the Maximally Entangled State of a Pair of Qubits",
  "authors": [
    "Jiangfeng Du",
    "Jing Zhu",
    "Mingjun Shi",
    "Xinhua Peng",
    "Dieter Suter"
  ],
  "doi": "10.1103/PhysRevA.76.042121",
  "categories": [
    "quant-ph"
  ],
  "abstract": "Quantum mechanical phase factors can be related to dynamical effects or to the geometrical properties of a trajectory in a given space - either parameter space or Hilbert space. Here, we experimentally investigate a quantum mechanical phase factor that reflects the topology of the SO(3) group: since rotations by $\\pi$ around antiparallel axes are identical, this space is doubly connected. Using pairs of nuclear spins in a maximally entangled state, we subject one of the spins to a cyclic evolution. If the corresponding trajectory in SO(3) can be smoothly deformed to a point, the quantum state at the end of the trajectory is identical to the initial state. For all other trajectories the quantum state changes sign.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2007-05-24T12:03:49.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "03.65.Vf",
      "03.67.Mn",
      "76.60.-k"
    ],
    "keywords": [
      "maximally entangled state",
      "experimental observation",
      "quantum mechanical phase factor",
      "topological phase",
      "quantum state changes sign"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review A",
      "year": 2007,
      "month": "Oct",
      "volume": 76,
      "number": 4,
      "pages": "042121"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2007PhRvA..76d2121D"
    }
  }
}