{
  "id": "cond-mat/9701022",
  "version": "v1",
  "published": "1997-01-06T14:04:59.000Z",
  "updated": "1997-01-06T14:04:59.000Z",
  "title": "Phase transitions in a frustrated XY model with zig-zag couplings",
  "authors": [
    "M. Benakli",
    "E. Granato"
  ],
  "comment": "11 pages, 9 figures, RevTex, to appear in Phys. Rev. B",
  "journal": "Phys. Rev. B 55, 8361 (97).",
  "doi": "10.1103/PhysRevB.55.8361",
  "categories": [
    "cond-mat.stat-mech",
    "cond-mat.supr-con"
  ],
  "abstract": "We study a new generalized version of the square-lattice frustrated XY model where unequal ferromagnetic and antiferromagnetic couplings are arranged in a zig-zag pattern. The ratio between the couplings $\\rho$ can be used to tune the system, continuously, from the isotropic square-lattice to the triangular-lattice frustrated XY model. The model can be physically realized as a Josephson-junction array with two different couplings, in a magnetic field corresponding to half-flux quanta per plaquette. Mean-field approximation, Ginzburg-Landau expansion and finite-size scaling of Monte Carlo simulations are used to study the phase diagram and critical behavior. Depending on the value of $\\rho$, two separate transitions or a transition line in the universality class of the XY-Ising model, with combined $Z_2$ and U(1) symmetries, takes place. In particular, the phase transitions of the standard square-lattice and triangular-lattice frustrated XY models correspond to two different cuts through the same transition line. Estimates of the chiral ($Z_2$) critical exponents on this transition line deviate significantly from the pure Ising values, consistent with that along the critical line of the XY-Ising model. This suggests that a frustrated XY model or Josephson-junction array with a zig-zag coupling modulation can provide a physical realization of the XY-Ising model critical line.",
  "revisions": [
    {
      "version": "v1",
      "updated": "1997-01-06T14:04:59.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "phase transitions",
      "zig-zag coupling",
      "xy-ising model",
      "triangular-lattice frustrated xy models correspond",
      "josephson-junction array"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Phys. Rev. B"
    },
    "note": {
      "typesetting": "RevTeX",
      "pages": 11,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}