Magnetic states of discontinuous Co80Fe20Al2O3 Multilayers

نویسندگان

  • Christian Binek
  • S. Sahoo
  • O. Sichelschmidt
  • O. Petracic
  • Ch. Binek
  • W. Kleemann
  • J. B. Sousa
  • S. Cardoso
  • P. P. Freitas
چکیده

Discontinuous metal–insulator multilayers [Co80Fe20(t)/Al2O3(3 nm)]n were studied by SQUID magnetometry and AC susceptometry. CoFe forms ferromagnetic particles in the Al2O3 matrix. In this paper, we focus on the field dependence of the AC susceptibility of samples with t 1⁄4 1:3 nm. We find strong evidence for transitions from a superparato a superferromagnetic and, finally, to a reentrant superspin glass state. r 2002 Elsevier Science B.V. All rights reserved.

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تاریخ انتشار 2017