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Journal of Nanoparticle Research

, Volume 13, Issue 11, pp 5587–5593 | Cite as

Investigation of the magnetization reversal of a magnetic dot array of Co/Pt multilayers

  • P. Krone
  • D. Makarov
  • A. Cattoni
  • G. Faini
  • A.-M. Haghiri-Gosnet
  • I. Knittel
  • U. Hartmann
  • T. Schrefl
  • M. Albrecht
Research Paper

Abstract

The magnetization reversal behavior of a dot array consisting of Co/Pt multilayers with perpendicular magnetic anisotropy was investigated. The size of the dots was varied from 200 nm down to 40 nm, while keeping the filling factor constant at about 0.16. The structural properties were determined by scanning electron microscopy, whereas the magnetic investigation was performed using SQUID and MFM techniques. It was observed that the dot size has a severe impact on the magnetization reversal mechanism where only the smallest dots with a size of 40 nm are found to be in a magnetic single-domain state. Moreover, the patterning process leads to a degradation of the multilayer, leading to a reduction of the switching field and an increase of the switching field distribution with decreasing dot size. In addition, micromagnetic simulations were performed to understand the magnetization reversal mechanism in more detail.

Keywords

Bit patterned media Micromagnetism Recording media Magnetization reversal Nanolayers 

Notes

Acknowledgments

The authors acknowledge E. Preiss (University of Saarbrücken) for help with the in-field MFM measurements, and R. Magerle (TU Chemnitz) for the opportunity to perform AFM/MFM studies. This work is financially supported by the European Commission via the FP7-project TERAMAGSTOR (No. 224001).

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Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • P. Krone
    • 1
  • D. Makarov
    • 1
    • 2
  • A. Cattoni
    • 3
  • G. Faini
    • 3
  • A.-M. Haghiri-Gosnet
    • 3
  • I. Knittel
    • 4
  • U. Hartmann
    • 4
  • T. Schrefl
    • 5
  • M. Albrecht
    • 1
  1. 1.Institute of PhysicsChemnitz University of TechnologyChemnitzGermany
  2. 2.Institute for Integrative NanosciencesIFW DresdenDresdenGermany
  3. 3.CNRS—Laboratoire de Photonique et de NanostructuresMarcoussisFrance
  4. 4.Institute of Experimental PhysicsSaarland UniversitySaarbrückenGermany
  5. 5.St. Pölten University of Applied ScienceSt. PöltenAustria

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