{
  "id": "cond-mat/9908150",
  "version": "v1",
  "published": "1999-08-10T12:37:45.000Z",
  "updated": "1999-08-10T12:37:45.000Z",
  "title": "Magnetic relaxation in a classical spin chain as model for nanowires",
  "authors": [
    "D. Hinzke",
    "U. Nowak"
  ],
  "comment": "8 pages, Revtex, 8 Figures included",
  "categories": [
    "cond-mat.stat-mech"
  ],
  "abstract": "With decreasing particle size, different mechanisms dominate the thermally activated magnetization reversal in ferromagnetic particles. We investigate some of these mechanisms for the case of elongated, single-domain nanoparticles which we describe by a classical Heisenberg spin chain driven by an external magnetic field. For sufficiently small system size the magnetic moments rotate coherently. With increasing size a crossover to a reversal due to soliton-antisoliton nucleation sets in. For even larger systems many of these soliton-antisoliton pairs nucleate at the same time. These effects give rise to a complex size dependence of the energy barriers and characteristic time scales of the relaxation. We study these quantities using Monte Carlo simulations as well as a direct integration of the Landau-Lifshitz-Gilbert equation of motion with Langevin dynamics and we compare our results with asymptotic solutions for the escape rate following from the Fokker-Planck equation. Also, we investigate the crossover from coherent rotation to soliton-antisoliton nucleation and multi-droplet nucleation, especially its dependence on the system size, the external field and the anisotropy of the system.",
  "revisions": [
    {
      "version": "v1",
      "updated": "1999-08-10T12:37:45.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "classical spin chain",
      "magnetic relaxation",
      "classical heisenberg spin chain driven",
      "soliton-antisoliton nucleation",
      "magnetic moments rotate"
    ],
    "note": {
      "typesetting": "RevTeX",
      "pages": 8,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "1999cond.mat..8150H"
    }
  }
}