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Journal of Materials Science

, Volume 46, Issue 13, pp 4638–4645 | Cite as

Morphological and magnetic properties of TiO2/Fe50Co50 composite films

  • A. Kulkarni
  • V. S. K. Chakravadhanula
  • V. Duppel
  • D. Meyners
  • V. Zaporojtchenko
  • T. Strunskus
  • L. Kienle
  • E. Quandt
  • F. Faupel
Article

Abstract

Nanocomposites of FeCo and TiO2 with wide range of metal volume fractions (MVFs) were prepared by co-sputtering. High resolution transmission electron microscopy analysis reveals that the microstructure of the nanocomposites depends on the MVF which determines the particle size and separation. FeCo nanoparticles are amorphous at lower MVF whereas crystallites are present at higher MVF. Likewise, the magnetic characteristics of these films depend on the MVF. At low MVF, composite films exhibit superparamagnetism whereas at high MVF, coalescence of crystalline nanoparticles results in the opening up of hysteresis loop. These composite films show a considerable room temperature tunnel magnetoresistance and being proportional to the square of the normalized magnetization (M/Ms)2.

Keywords

Composite Film Select Area Electron Diffraction Pattern Aged Film Granular Film Langevin Function 

Notes

Acknowledgements

Financial support by the German Science Foundation (DFG) through the Collaborative Research Center (SFB) 677 “Function by Switching”—Project C7 is gratefully acknowledged. The authors thank Prof. Dr. Dr. h. c. Mult. A. Simon for enabling TEM experiments.

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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • A. Kulkarni
    • 1
  • V. S. K. Chakravadhanula
    • 2
  • V. Duppel
    • 4
  • D. Meyners
    • 3
  • V. Zaporojtchenko
    • 1
  • T. Strunskus
    • 1
  • L. Kienle
    • 2
  • E. Quandt
    • 3
  • F. Faupel
    • 1
  1. 1.Institute for Materials Science—Multicomponent Materials, Faculty of EngineeringUniversity of KielKielGermany
  2. 2.Institute for Materials Science—Synthesis and Real Structures, Faculty of EngineeringUniversity of KielKielGermany
  3. 3.Institute for Materials Science—Inorganic Functional Materials, Faculty of EngineeringUniversity of KielKielGermany
  4. 4.Max Planck Institute for Solid State ResearchStuttgartGermany

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