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Title: Structural and magnetic properties of epitaxially grown Ge{sub 1-x}Fe{sub x} thin films: Fe concentration dependence

Abstract

Ge{sub 1-x}Fe{sub x} films (x=2.0%-24.0%) grown by low-temperature molecular beam epitaxy were shown to have a diamond-type crystal structure without any other crystallographic phase of precipitates, although they contain slightly nonuniform Fe distribution and tiny stacking fault defects. The lattice constant decreases linearly with increasing the Fe content x from 0% to 13.0%, and is saturated for x>13.0%. The Curie temperature (T{sub C}) increases in proportion to x ({<=}13.0%) and is saturated for x>13.0%. The maximum T{sub C} value was {approx}170 K at x>13.0%. The structural and magnetic properties indicate that Ge{sub 1-x}Fe{sub x} is an 'intrinsic' ferromagnetic semiconductor.

Authors:
; ;  [1];  [2];  [3]
  1. Department of Electronic Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)
  2. (Japan) and SORST, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi-shi, Saitama 332-0012 (Japan)
  3. (Japan) and Department of Electronics and Applied Physics, Tokyo Institute of Technology, 4259-G2-14 Nagatsuta, Yokohama, Kanagawa 226-8502 (Japan)
Publication Date:
OSTI Identifier:
20960182
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 13; Other Information: DOI: 10.1063/1.2718270; (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; CRYSTAL GROWTH; CRYSTALLOGRAPHY; CURIE POINT; DIAMONDS; FERROMAGNETIC MATERIALS; GERMANIUM COMPOUNDS; IRON COMPOUNDS; LATTICE PARAMETERS; LAYERS; MAGNETIC PROPERTIES; MAGNETIC SEMICONDUCTORS; MOLECULAR BEAM EPITAXY; PRECIPITATION; STACKING FAULTS; TEMPERATURE RANGE 0065-0273 K; THIN FILMS

Citation Formats

Shuto, Yusuke, Tanaka, Masaaki, Sugahara, Satoshi, Department of Electronic Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, and Imaging Science and Engineering Laboratory, Tokyo Institute of Technology, 4259-G2-14 Nagatsuta, Yokohama, Kanagawa 226-8502. Structural and magnetic properties of epitaxially grown Ge{sub 1-x}Fe{sub x} thin films: Fe concentration dependence. United States: N. p., 2007. Web. doi:10.1063/1.2718270.
Shuto, Yusuke, Tanaka, Masaaki, Sugahara, Satoshi, Department of Electronic Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, & Imaging Science and Engineering Laboratory, Tokyo Institute of Technology, 4259-G2-14 Nagatsuta, Yokohama, Kanagawa 226-8502. Structural and magnetic properties of epitaxially grown Ge{sub 1-x}Fe{sub x} thin films: Fe concentration dependence. United States. doi:10.1063/1.2718270.
Shuto, Yusuke, Tanaka, Masaaki, Sugahara, Satoshi, Department of Electronic Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, and Imaging Science and Engineering Laboratory, Tokyo Institute of Technology, 4259-G2-14 Nagatsuta, Yokohama, Kanagawa 226-8502. Mon . "Structural and magnetic properties of epitaxially grown Ge{sub 1-x}Fe{sub x} thin films: Fe concentration dependence". United States. doi:10.1063/1.2718270.
@article{osti_20960182,
title = {Structural and magnetic properties of epitaxially grown Ge{sub 1-x}Fe{sub x} thin films: Fe concentration dependence},
author = {Shuto, Yusuke and Tanaka, Masaaki and Sugahara, Satoshi and Department of Electronic Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 and Imaging Science and Engineering Laboratory, Tokyo Institute of Technology, 4259-G2-14 Nagatsuta, Yokohama, Kanagawa 226-8502},
abstractNote = {Ge{sub 1-x}Fe{sub x} films (x=2.0%-24.0%) grown by low-temperature molecular beam epitaxy were shown to have a diamond-type crystal structure without any other crystallographic phase of precipitates, although they contain slightly nonuniform Fe distribution and tiny stacking fault defects. The lattice constant decreases linearly with increasing the Fe content x from 0% to 13.0%, and is saturated for x>13.0%. The Curie temperature (T{sub C}) increases in proportion to x ({<=}13.0%) and is saturated for x>13.0%. The maximum T{sub C} value was {approx}170 K at x>13.0%. The structural and magnetic properties indicate that Ge{sub 1-x}Fe{sub x} is an 'intrinsic' ferromagnetic semiconductor.},
doi = {10.1063/1.2718270},
journal = {Applied Physics Letters},
number = 13,
volume = 90,
place = {United States},
year = {Mon Mar 26 00:00:00 EDT 2007},
month = {Mon Mar 26 00:00:00 EDT 2007}
}
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