{
  "id": "cond-mat/0511606",
  "version": "v1",
  "published": "2005-11-24T14:53:41.000Z",
  "updated": "2005-11-24T14:53:41.000Z",
  "title": "Two-dimensional quantum spin-1/2 Heisenberg model with competing interactions",
  "authors": [
    "J. Ricardo de Sousa",
    "N. S. Branco"
  ],
  "comment": "4 pages, 1 figure",
  "journal": "Phys. Rev. B, vol. 72, 134421 (2005)",
  "doi": "10.1103/PhysRevB.72.134421",
  "categories": [
    "cond-mat.stat-mech"
  ],
  "abstract": "We study the quantum spin-1/2 Heisenberg model in two dimensions, interacting through a nearest-neighbor antiferromagnetic exchange ($J$) and a ferromagnetic dipolar-like interaction ($J_d$), using double-time Green's function, decoupled within the random phase approximation (RPA). We obtain the dependence of $k_B T_c/J_d$ as a function of frustration parameter $\\delta$, where $T_c$ is the ferromagnetic (F) transition temperature and $\\delta$ is the ratio between the strengths of the exchange and dipolar interaction (i.e., $\\delta = J/J_d$). The transition temperature between the F and paramagnetic phases decreases with $\\delta$, as expected, but goes to zero at a finite value of this parameter, namely $\\delta = \\delta_c = \\pi /8$. At T=0 (quantum phase transition), we analyze the critical parameter $\\delta_c(p)$ for the general case of an exchange interaction in the form $J_{ij}=J_d/r_{ij}^{p}$, where ferromagnetic and antiferromagnetic phases are present.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2005-11-24T14:53:41.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "heisenberg model",
      "two-dimensional quantum",
      "competing interactions",
      "transition temperature",
      "double-time greens function"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Phys. Rev. B"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 4,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}