Investigation of exchange bias effect of fine cobalt particles with oxidized surface

  • S. A. NepijkoEmail author
  • A. Petrov
  • D. Kondrakhova
  • I. Yu. Protsenko
  • H. J. Elmers
  • G. Schönhense
Research Paper


Phase characteristics of the partially oxidized cobalt particles were investigated. It is shown that the studied system consists of Co, CoO, and Co3O4 phases. The paper presents results for the magnetic characteristics of Co particles covered by a CoO shell. Magnetic measurements were performed at 77 K. It is shown that the shapes of the hysteresis loop of the investigated system are different for different cases of cooling, with and without applications of external magnetic field. Structural investigations were performed on single particles.


Coercive force Exchange anisotropy Magnetic hysteresis Nanoparticle 



The study has been performed within the framework of the scientific and technical cooperation between the Institute of Physics of Johannes Guttenberg University (Mainz, Germany) and Sumy State University (Sumy, Ukraine).


  1. Albrecht M, Ganesan S, Rettner CT, Moser A, Best ME, White RL, Terris BD (2003) Patterned perpendicular and longitudinal media: a magnetic recording study. IEEE Trans Magn 39:2323–2325CrossRefGoogle Scholar
  2. Giri S, Patra M, Majumdar S (2011) Exchange bias effect in alloys and compounds. J Phys 23:073201Google Scholar
  3. Hinzke D, Nowak U (1999) Monte Carlo simulation of magnetization switching in a Heisenberg model for small ferromagnetic particles. Comput Phys Commun 121–122:334–337CrossRefGoogle Scholar
  4. Huang Z, Chen Z, Zhang F, Du Y (2004) Magnetization and configurational anisotropy in magnetic clusters: Monte Carlo simulation. Eur Phys J B 37:177–185CrossRefGoogle Scholar
  5. Jacobs IS, Bean CP (1963) Fine particles, thin films and exchange anisotropy. In: Rado GT, Suhl H (eds) Magnetism, vol 3. Academic, New York, pp 271–350Google Scholar
  6. Kneller E (1966) Theorie der Magnetisierungskurve kleiner Kristalle. In: Flügge S (ed) Encyclopedia of Physics, vol 18/2 (Ferromagnetism). Springer, Berlin, pp 438–544Google Scholar
  7. Kneller E (1968) Magnetic-interaction effects in fine-particle assemblies and in thin films. J Appl Phys 39:945–956CrossRefGoogle Scholar
  8. Meiklejohn WH (1962) Exchange anisotropy—a review. J Appl Phys 33:1328–1335CrossRefGoogle Scholar
  9. Meiklejohn WH, Bean CP (1956) New magnetic anisotropy. Phys Rev 102:1413–1414CrossRefGoogle Scholar
  10. Meiklejohn WH, Bean CP (1957) New magnetic anisotropy. Phys Rev 105:904–913CrossRefGoogle Scholar
  11. Nepijko SA (1985) Physical properties of small particles. Naukova Dumka, Kiev (Russian)Google Scholar
  12. Nogués J, Sort J, Langlais V, Skumryev V, Suriñach S, Muñoz JS, Baró MD (2005) Exchange bias in nanostructures. Phys Rep 422:65–117CrossRefGoogle Scholar
  13. Petrov AE, Petinov VI, Plate IV, Fedorova EA, Gen MY (1971) Magnetic properties of small aerosol cobalt particles. Sov Phys Solid State 13:1318–1322Google Scholar
  14. Petrov A, Kudrenitskis I, Belogurov S, Nepijko S (1996) Exchange anisotropy of cobalt fine particles. Ann Phys 508:627–632CrossRefGoogle Scholar
  15. Shtrikman S, Treves D (1963) Magnetic symmetry and electron nucleus interactions in magnetic crystals. Phys Lett 4:294–295CrossRefGoogle Scholar
  16. Tsymbal EY, Mryasov ON, LeClair PR (2003) Spin-dependent tunnelling in magnetic tunnel junctions. J Phys 15:R109–R142Google Scholar
  17. Vlasov KB, Volkenshtein NV, Vonsovskii SV, Mitsek AI, Turchinskaya MI (1965) Unidirectional anisotropy. Bull Acad Sci USSR Phys Ser (USA) 28:338–344Google Scholar
  18. Zhang Z (2007) Surface effects in the energy loss near edge structure of different cobalt oxides. Ultramicroscopy 107:598–603CrossRefGoogle Scholar
  19. Zianni X, Trohidou KN (1998) Monte Carlo simulations on the coercive behaviour of oxide coated ferromagnetic particles. J Phys 10:7475–7483Google Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  • S. A. Nepijko
    • 1
    Email author
  • A. Petrov
    • 2
  • D. Kondrakhova
    • 3
  • I. Yu. Protsenko
    • 3
  • H. J. Elmers
    • 1
  • G. Schönhense
    • 1
  1. 1.Institute of Physics, University of MainzMainzGermany
  2. 2.Institute of Solid State Physics, University of LatviaRīgaLatvia
  3. 3.Sumy State UniversitySumyCIS/Ukraine

Personalised recommendations