Spin polarization of Co{sub 2}MnGe and Co{sub 2}MnSi thin films with A2 and L2{sub 1} structures

doi:10.1063/1.2409775

Title: Spin polarization of Co{sub 2}MnGe and Co{sub 2}MnSi thin films with A2 and L2{sub 1} structures

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Abstract

Spin polarizations (P) of polycrystalline Co{sub 2}MnGe and Co{sub 2}MnSi films that were sputter deposited on thermally oxidized Si substrates at various substrate temperatures (T{sub s}) were measured by the point contact Andreev reflection technique. While continuous films were grown at T{sub s}=500 degree sign C with the L2{sub 1} structure, Mn-deficit islands were formed at T{sub s}>700 degree sign C. P showed strong dependence on the state of order of the alloys; P=0.58 for L2{sub 1} ordered Co{sub 2}MnGe, P=0.35 for A2 Co{sub 2}MnGe, P=0.54 for L2{sub 1} ordered Co{sub 2}MnSi, and P=0.52 for A2 Co{sub 2}MnSi. The experimentally determined P values of the L2{sub 1} ordered films are lower than the theoretical predictions, which is attributed to the imperfect L2{sub 1} ordering.

Authors:

Rajanikanth, A.; Takahashi, Y. K.; Hono, K. ^[1]; National Institute for Materials Science ^[2]

Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-0047 (Japan)
(NIMS), Tsukuba 305-0047 (Japan)

Publication Date:: Mon Jan 15 00:00:00 EST 2007

OSTI Identifier:: 20982641

Resource Type:: Journal Article

Resource Relation:: Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 2; Other Information: DOI: 10.1063/1.2409775; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; COBALT ALLOYS; ELECTRIC CONTACTS; FERROMAGNETIC MATERIALS; GERMANIUM ALLOYS; MANGANESE ALLOYS; POLYCRYSTALS; SILICON ALLOYS; SPECTROSCOPY; SPIN; SPIN ORIENTATION; SPUTTERING; SUBSTRATES; SURFACE COATING; THIN FILMS

Citation Formats


                    Rajanikanth, A., Takahashi, Y. K., Hono, K., and National Institute for Materials Science. Spin polarization of Co{sub 2}MnGe and Co{sub 2}MnSi thin films with A2 and L2{sub 1} structures.  United States: N. p., 2007. 
        Web.  doi:10.1063/1.2409775.

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                    Rajanikanth, A., Takahashi, Y. K., Hono, K., & National Institute for Materials Science. Spin polarization of Co{sub 2}MnGe and Co{sub 2}MnSi thin films with A2 and L2{sub 1} structures.  United States.  doi:10.1063/1.2409775.

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                    Rajanikanth, A., Takahashi, Y. K., Hono, K., and National Institute for Materials Science. Mon .  
        "Spin polarization of Co{sub 2}MnGe and Co{sub 2}MnSi thin films with A2 and L2{sub 1} structures".  United States.  
        doi:10.1063/1.2409775.

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@article{osti_20982641,

  title        = {Spin polarization of Co{sub 2}MnGe and Co{sub 2}MnSi thin films with A2 and L2{sub 1} structures},

  author       = {Rajanikanth, A. and Takahashi, Y. K. and Hono, K. and National Institute for Materials Science},

  abstractNote = {Spin polarizations (P) of polycrystalline Co{sub 2}MnGe and Co{sub 2}MnSi films that were sputter deposited on thermally oxidized Si substrates at various substrate temperatures (T{sub s}) were measured by the point contact Andreev reflection technique. While continuous films were grown at T{sub s}=500 degree sign C with the L2{sub 1} structure, Mn-deficit islands were formed at T{sub s}>700 degree sign C. P showed strong dependence on the state of order of the alloys; P=0.58 for L2{sub 1} ordered Co{sub 2}MnGe, P=0.35 for A2 Co{sub 2}MnGe, P=0.54 for L2{sub 1} ordered Co{sub 2}MnSi, and P=0.52 for A2 Co{sub 2}MnSi. The experimentally determined P values of the L2{sub 1} ordered films are lower than the theoretical predictions, which is attributed to the imperfect L2{sub 1} ordering.},

  doi          = {10.1063/1.2409775},

  journal      = {Journal of Applied Physics},

  number       = 2,

  volume       = 101,

  place        = {United States},

  year         = {Mon Jan 15 00:00:00 EST 2007},

  month        = {Mon Jan 15 00:00:00 EST 2007}

}

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DOI: 10.1063/1.2409775

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