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Submicron Size Particles of Magnetic Films and Multilayers

  • M. Hanson
  • O. Kazakova
Chapter
Part of the NATO Science Series book series (NAII, volume 91)

Abstract

The area between the micro- and macroscopic ranges of magnetism offers an exciting field for research and development. The design of magnets for small-scale applications requires several physical parameters to be simultaneously controlled and matched to each other. First one should control the exchange energy, the crystalline anisotropy and the atomic magnetic moment; material parameters governing e. g. the ordering temperature and magnetization of the material. This may be accomplished by applying modern preparation techniques to make thin films and layered materials, yielding a variety of intrinsic magnetic properties [1]. Second, the demagnetizing effects that are inevitably introduced when the lateral extensions of the material are limited must be incorporated in the design to yield the proper zero-field state as well as dynamic response [2]. There are many questions to answer about the zero-field state of a magnetic particle, for instance how the critical sizes for formation of a single domain (SD) can be reached. SD particles with two possible orientations of their moment in zero field — a binary bit — are suggested as building blocks of a novel magnetic memory [3]. At the same time as a stable zero-field state is obtained, magnetization reversal should occur at an appropriate field with a narrow distribution of switching fields among the particles.

Keywords

Multilayer Film Hysteresis Curve Epitaxial Film Magnetocrystalline Anisotropy Magnetic Force Microscopy 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media Dordrecht 2003

Authors and Affiliations

  • M. Hanson
    • 1
  • O. Kazakova
    • 1
  1. 1.Department of Solid State PhysicsChalmers University of Technology and Göteborg UniversityGöteborgSweden

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