Two-dimensional modelling of soft ferromagnetic films

被引:40
作者
DeSimone, A
Kohn, RV
Müller, S
Otto, F
Schäfer, R
机构
[1] Max Planck Inst Math Sci, D-04103 Leipzig, Germany
[2] Courant Inst Math Sci, New York, NY 10012 USA
[3] Univ Bonn, Inst Angew Math, D-53115 Bonn, Germany
[4] Inst Festkorper & Werkstofforsch, D-01069 Dresden, Germany
来源
PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES | 2001年 / 457卷 / 2016期
关键词
micromagnetics; thin films; permalloy; gamma convergence; domain structures;
D O I
10.1098/rspa.2001.0846
中图分类号
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号
07 ; 0710 ; 09 ;
摘要
We examine the response of a soft ferromagnetic film to ail in-plane applied magnetic field by means of both theory and experiment. In the thin-film limit, we uncover a separation of scales in the rough energy landscape of micromagnetics: leading-order terms generate constraints which eliminate degrees of freedom, terms of second order in the film thickness lead to a (new) reduced variational model, higher-order terms are related to wall, vortex and anisotropy energies. We propose a new strategy to compute low-energy domain patterns, which proceeds in two steps: we determine first the magnetic charge density by solving a convex variational problem, then we construct an associated magnetization field using a robust numerical method. Experimental results show good agreement with the theory. Our analysis is consistent with prior work by van den Berg and by Bryant and Suhl, but it goes much further; in particular it applies even for large fields which penetrate the sample.
引用
收藏
页码:2983 / 2991
页数:9
相关论文
共 20 条
  • [1] [Anonymous], 1996, LEVEL SET METHODS
  • [2] The distance function and defect energy
    Aviles, P
    Giga, Y
    [J]. PROCEEDINGS OF THE ROYAL SOCIETY OF EDINBURGH SECTION A-MATHEMATICS, 1996, 126 : 923 - 938
  • [3] Bertotti G., 1998, Hysteresis in Magnetism
  • [4] USING MULTIPOLES DECREASES COMPUTATION TIME FOR MAGNETOSTATIC SELF-ENERGY
    BLUE, JL
    SCHEINFEIN, MR
    [J]. IEEE TRANSACTIONS ON MAGNETICS, 1991, 27 (06) : 4778 - 4780
  • [5] MAGNETIZATION AND DOMAIN-STRUCTURE OF CYLINDERS AND SPHERES IN SUBSATURATING FIELDS
    BRYANT, P
    SUHL, H
    [J]. APPLIED PHYSICS LETTERS, 1989, 54 (01) : 78 - 80
  • [6] De Giorgi E., 1975, Atti della Accad. Nazionale dei Lincei. Cl. Sci. Fis. Mat. Natur. Rend. Ser, V58, P842
  • [7] DESIMONE A, 2001, UNPUB
  • [8] Evans L.C., 1998, PARTIAL DIFFERENTIAL
  • [9] Micromagnetics of very thin films
    Gioia, G
    James, RD
    [J]. PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, 1997, 453 (1956): : 213 - 223
  • [10] Singular perturbation and the energy of folds
    Jin, W
    Kohn, RV
    [J]. JOURNAL OF NONLINEAR SCIENCE, 2000, 10 (03) : 355 - 390