Transport properties of discontinuous Co{sub 80}Fe{sub 20}/Al{sub 2}O{sub 3} multilayers, prepared by ion beam sputtering

Kakazei, G N; Freitas, P P; Cardoso, S; Lopes, A M.L.; Pereira de Azevedo, M M; Pogorelov, Y G; Sousa, J B

doi:10.1109/20.801017

Title: Transport properties of discontinuous Co{sub 80}Fe{sub 20}/Al{sub 2}O{sub 3} multilayers, prepared by ion beam sputtering

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Abstract

Ion beam sputtered Co{sub 80}Fe{sub 20}(t)/Al{sub 2}O{sub 3}(30 {angstrom}) multilayers were obtained. The Co{sub 80}Fe{sub 20} layers become discontinuous for nominal thicknesses T {le} 18{angstrom}. Tunnel magnetoresistance was measured in CIP and CPP geometries, reaching up to 6.5% at room temperature and 11% at 15 K, for as-deposited films in CIP geometry. The temperature dependence of MR was found quite different for the two geometries: fairly strong in the CIP case and almost absent in the CPP geometry. A model is proposed to explain these large differences in behavior.

Authors:: Kakazei, G N; Freitas, P P; Cardoso, S; Lopes, A M.L.; Pereira de Azevedo, M M; Pogorelov, Y G; Sousa, J B

Publication Date:: Wed Sep 01 00:00:00 EDT 1999

Research Org.:: Univ. do Porto (PT)

OSTI Identifier:: 20000664

Resource Type:: Journal Article

Journal Name:: IEEE Transactions on Magnetics (Institute of Electrical and Electronics Engineers)

Additional Journal Information:: Journal Volume: 35; Journal Issue: 5Pt1; Conference: 1999 international magnetics conference (Intermag '99), Kyongju (KR), 05/18/1999--05/21/1999; Other Information: PBD: Sep 1999; Journal ID: ISSN 0018-9464

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; LAYERS; COBALT BASE ALLOYS; IRON ALLOYS; ALUMINIUM OXIDES; COMPOSITE MATERIALS; MAGNETORESISTANCE; TUNNEL EFFECT; TEMPERATURE DEPENDENCE; MATHEMATICAL MODELS

Citation Formats


                    Kakazei, G N, Freitas, P P, Cardoso, S, Lopes, A M.L., Pereira de Azevedo, M M, Pogorelov, Y G, and Sousa, J B. Transport properties of discontinuous Co{sub 80}Fe{sub 20}/Al{sub 2}O{sub 3} multilayers, prepared by ion beam sputtering.  United States: N. p., 1999. 
        Web.  doi:10.1109/20.801017.

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                    Kakazei, G N, Freitas, P P, Cardoso, S, Lopes, A M.L., Pereira de Azevedo, M M, Pogorelov, Y G, & Sousa, J B. Transport properties of discontinuous Co{sub 80}Fe{sub 20}/Al{sub 2}O{sub 3} multilayers, prepared by ion beam sputtering.  United States.  https://doi.org/10.1109/20.801017

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                    Kakazei, G N, Freitas, P P, Cardoso, S, Lopes, A M.L., Pereira de Azevedo, M M, Pogorelov, Y G, and Sousa, J B. 1999.  
        "Transport properties of discontinuous Co{sub 80}Fe{sub 20}/Al{sub 2}O{sub 3} multilayers, prepared by ion beam sputtering".  United States.  https://doi.org/10.1109/20.801017.

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@article{osti_20000664,

  title        = {Transport properties of discontinuous Co{sub 80}Fe{sub 20}/Al{sub 2}O{sub 3} multilayers, prepared by ion beam sputtering},

  author       = {Kakazei, G N and Freitas, P P and Cardoso, S and Lopes, A M.L. and Pereira de Azevedo, M M and Pogorelov, Y G and Sousa, J B},

  abstractNote = {Ion beam sputtered Co{sub 80}Fe{sub 20}(t)/Al{sub 2}O{sub 3}(30 {angstrom}) multilayers were obtained. The Co{sub 80}Fe{sub 20} layers become discontinuous for nominal thicknesses T {le} 18{angstrom}. Tunnel magnetoresistance was measured in CIP and CPP geometries, reaching up to 6.5% at room temperature and 11% at 15 K, for as-deposited films in CIP geometry. The temperature dependence of MR was found quite different for the two geometries: fairly strong in the CIP case and almost absent in the CPP geometry. A model is proposed to explain these large differences in behavior.},

  doi          = {10.1109/20.801017},

  url          = {https://www.osti.gov/biblio/20000664},
  journal      = {IEEE Transactions on Magnetics (Institute of Electrical and Electronics Engineers)},

  issn         = {0018-9464},

  number       = 5Pt1,

  volume       = 35,

  place        = {United States},

  year         = {Wed Sep 01 00:00:00 EDT 1999},

  month        = {Wed Sep 01 00:00:00 EDT 1999}

}

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