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

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:
; ;  [1];  [2]
  1. Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-0047 (Japan)
  2. (NIMS), Tsukuba 305-0047 (Japan)
Publication Date:
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.
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.
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.
@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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