{
  "id": "1212.5174",
  "version": "v1",
  "published": "2012-12-20T18:13:17.000Z",
  "updated": "2012-12-20T18:13:17.000Z",
  "title": "Dynamic heterogeneities above and below the mode-coupling temperature. Evidence of a dynamic crossover",
  "authors": [
    "Elijah Flenner",
    "Grzegorz Szamel"
  ],
  "comment": "To appear in J. Chem. Phys. \"Special Topic Issue on the Glass Transition\"",
  "categories": [
    "cond-mat.stat-mech"
  ],
  "abstract": "We examine dynamic heterogeneities in a model glass-forming fluid, a binary harmonic sphere mixture, above and below the mode-coupling temperature T_c. We calculate the ensemble independent susceptibility chi_4(tau_alpha) and the dynamic correlation length xi_4(tau_alpha) at the alpha-relaxation time tau_alpha. We also examine in detail the temperature dependence of tau_alpha and the diffusion coefficient D. For higher temperatures we find that the standard Stokes-Einstein relationship, D ~ tau_alpha^{-1}, holds, but at lower temperatures a fractional Stokes-Einstein relationship, D ~ tau_alpha^{-sigma} with sigma = 0.65, emerges. By examining the relationships between tau_alpha, D, chi_4(tau_alpha), and xi_4(tau_alpha) we determine that the emergence of the fractional Stokes-Einstein relationship is accompanied by a dynamic crossover from tau_alpha ~ e^{k_2 xi_4} at higher temperatures to tau_alpha ~ e^{k_1 xi_4^{3/2}} at lower temperatures.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2012-12-20T18:13:17.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "66.10.C-",
      "61.20.Ja",
      "61.25.Em",
      "64.75.Ef"
    ],
    "keywords": [
      "dynamic heterogeneities",
      "dynamic crossover",
      "mode-coupling temperature",
      "fractional stokes-einstein relationship",
      "binary harmonic sphere mixture"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1063/1.4773321",
      "journal": "Journal of Chemical Physics",
      "year": 2013,
      "month": "Mar",
      "volume": 138,
      "number": 12
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2013JChPh.138lA523F"
    }
  }
}