{
  "id": "cond-mat/0509721",
  "version": "v3",
  "published": "2005-09-28T09:42:15.000Z",
  "updated": "2006-01-02T09:57:35.000Z",
  "title": "Continuous unitary transformations in two-level boson systems",
  "authors": [
    "S. Dusuel",
    "J. Vidal",
    "J. M. Arias",
    "J. Dukelsky",
    "J. E. Garcia-Ramos"
  ],
  "comment": "27 pages, 16 figures, published version",
  "journal": "Phys. Rev. C 72, 064332 (2005)",
  "doi": "10.1103/PhysRevC.72.064332",
  "categories": [
    "cond-mat.stat-mech",
    "nucl-th",
    "quant-ph"
  ],
  "abstract": "Two-level boson systems displaying a quantum phase transition from a spherical (symmetric) to a deformed (broken) phase are studied. A formalism to diagonalize Hamiltonians with $O(2L+1)$ symmetry for large number of bosons is worked out. Analytical results beyond the simple mean-field treatment are deduced by using the continuous unitary transformations technique. In this scheme, a 1/N expansion for different observables is proposed and allows one to compute the finite-size scaling exponents at the critical point. Analytical and numerical results are compared and reveal the power of the present approach to compute the finite-size corrections in such a context.",
  "revisions": [
    {
      "version": "v3",
      "updated": "2006-01-02T09:57:35.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "21.60.Fw",
      "21.10.Re",
      "05.10.Cc",
      "75.40.Cx"
    ],
    "keywords": [
      "quantum phase transition",
      "simple mean-field treatment",
      "continuous unitary transformations technique",
      "large number",
      "two-level boson systems displaying"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Phys. Rev. C"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 27,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 693728
    }
  }
}