Advertisement

Journal of Electronic Materials

, Volume 48, Issue 3, pp 1461–1466 | Cite as

Magnetic Anisotropy and Switching Behavior of Fe3O4/CoFe2O4 Core/Shell Nanoparticles

  • R. DasEmail author
  • J. Robles
  • M. Glassell
  • V. Kalappattil
  • M. H. Phan
  • H. SrikanthEmail author
5th International Conference of Asian Union of Magnetics Societies
  • 41 Downloads
Part of the following topical collections:
  1. 5th International Conference of Asian Union of Magnetics Societies (IcAUMS)

Abstract

A uniform core/shell nanoparticle system composed of a soft magnetic core (Fe3O4) and a hard magnetic shell (CoFe2O4) was synthesized and characterized to understand how the shell influences the magnetism and exchange coupling of the system. In the case of Fe3O4(8 nm)/CoFe2O4(2 nm) core/shell nanoparticles, DC and AC susceptibility measurements revealed three features associated with the blocking temperatures of the core/shell system (TB-cs ∼  300 K), the CoFe2O4 shell (TB-s ∼ 200 K), and the Fe3O4 core (TB-c ∼ 50 K). Radio-frequency transverse susceptibility gave a direct probe of the effective magnetic anisotropy field (HK) and switching field (HS), as well as their temperature evolutions. Interestingly, we found that HK of the core/shell structure increased with decreasing temperature. HS was observed only below TB-s, which first decreased drastically with lowering temperature and then increased sharply below TB-c. This is attributed to the effect of a coercive field of CoFe2O4 on the spin flipping of Fe3O4 in the superparamagnetic state (TB-c < T < TB-s) and the blocked state (T < TB-c), respectively. Our study sheds light on the magnetic exchange coupling mechanism in core/shell nanoparticle systems and demonstrates the possibility of controlling the nanomagnetism of a soft magnetic core to which the hard magnetic shell is coupled in such systems.

Keywords

Core/shell nanoparticle magnetic anisotropy magnetic switching 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Notes

Acknowledgments

Research at the University of South Florida was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award No. DE-FG02-07ER46438. Joshua Robles acknowledges the financial support provided by the NSF Florida-Georgia Louis Stokes Alliance for Minority Participation (FGLSAMP) through Award No. HRD #1612347.

References

  1. 1.
    S.H. Moon, A.-H. Noh, J.-H. Lee, T.-H. Shin, Y. Lim, and J. Cheon, Nano Lett. 17, 800 (2017).CrossRefGoogle Scholar
  2. 2.
    H. Zeng, L. Li, J.P. Liu, Z.L. Wang, and S.H. Sun, Nature 420, 395 (2002).CrossRefGoogle Scholar
  3. 3.
    A. Lopez-Ortega, M. Estrader, G. Salazar-Alvarez, A.G. Roca, and J. Nogues, J. Phys. Rep. 553, 1 (2015).CrossRefGoogle Scholar
  4. 4.
    M.H. Phan, J. Alonso, H. Khurshid, P. Lampen-Kelley, S. Chandra, K.S. Repa, Z.N. Porshokouh, R. Das, Ò. Iglesias, and H. Srikanth, Nanomaterials 6, 221 (2016).CrossRefGoogle Scholar
  5. 5.
    S. Chandra, H. Khurshid, M.H. Phan, and H. Srikanth, Appl. Phys. Lett. 101, 232405 (2012).CrossRefGoogle Scholar
  6. 6.
    S. Chandra, H. Khurshid, W. Li, G.C. Hadjipanayis, M.H. Phan, and H. Srikanth, Phys. Rev. B 86, 1 (2012).CrossRefGoogle Scholar
  7. 7.
    Z. Nemati, H. Khurshid, J. Alonso, M.H. Phan, P. Mukherjee, and H. Srikanth, Nanotechnology 26, 406705 (2015).CrossRefGoogle Scholar
  8. 8.
    R.E. Rosensweig, J. Magn. Magn. Mater. 252, 370 (2002).CrossRefGoogle Scholar
  9. 9.
    J.H. Lee, J.-T. Jang, J.-S. Choi, S.H. Moon, S.-H. Noh, J.-W. Kim, J.-G. Kim, I.I.-S. Kim, K.I. Park, and J. Cheon, Nat. Nanotech. 6, 418 (2011).CrossRefGoogle Scholar
  10. 10.
    H. Khurshid, J. Alonso, Z. Nemati, M.H. Phan, P. Mukherjee, M.L. Fdez-Gubieda, J.M. Barandiarán, and H. Srikanth, J. Appl. Phys. 117, 17A33 (2015).CrossRefGoogle Scholar
  11. 11.
    S. Sun, H. Zeng, D.B. Robinson, S. Raoux, P.M. Rice, S.X. Wang, and G. Li, J. Am. Chem. Soc. 126, 273 (2014).CrossRefGoogle Scholar
  12. 12.
    V. Gavrilov-Isaac, S. Neveu, V. Dupuis, D. Talbot, V. Cabuil, http://arxiv.org/abs/1402.1950v1 (2014).
  13. 13.
    H. Srikanth, J. Wiggins, H. Rees, H. Srikanth, J. Wiggins, and H. Rees, Rev. Sci. Instrum. 70, 3097 (1999).CrossRefGoogle Scholar
  14. 14.
    N.A. Frey Huls, N.S. Bingham, M.H. Phan, H. Srikanth, D.D. Stauffer, and C. Leighton, Phys. Rev. B 83, 024406 (2011).CrossRefGoogle Scholar
  15. 15.
    N.A. Frey, S. Srinath, H. Srikanth, M. Varela, S. Pennycook, G.X. Miao, and A. Gupta, Phys. Rev. B 74, 024420 (2006).CrossRefGoogle Scholar
  16. 16.
    S. Chandra, R. Das, V. Kalappattil, T. Eggers, C. Harnagea, R. Nechache, M.H. Phan, F. Rosei, and H. Srikanth, Nanoscale 9, 7858 (2017).CrossRefGoogle Scholar
  17. 17.
    R. Das, J. Alonso, Z.N. Porshokouh, V. Kalappattil, D. Torres, M.H. Phan, E. Garaio, J.Á. García, J.L.S. Llamazares, and H. Srikanth, J. Phys. Chem. C 120, 10086 (2016).CrossRefGoogle Scholar
  18. 18.
    A. Aharoni, E.H. Frei, S. Shtrikman, and D. Treves, Bull. Res. Counc. Isr. 6A, 215 (1957).Google Scholar

Copyright information

© The Minerals, Metals & Materials Society 2018

Authors and Affiliations

  1. 1.Department of PhysicsUniversity of South FloridaTampaUSA

Personalised recommendations