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Title: High in-plane anisotropy of epitaxial CoPt(110) alloy films prepared by cosputtering or molecular beam epitaxy on MgO

Abstract

We present structural and magnetic properties of three sets of structures: as-deposited CoPt films cosputtered at 900 K on MgO(110) substrates with a Pt(110) buffer layer and CoPt films deposited by molecular beam epitaxy directly on MgO(110) substrates at 900 K, as prepared and annealed at 900 K. All layers have the L1{sub 0} tetragonal structure. The chemical long-range ordering for the as-deposited CoPt films is incomplete in contrast with the annealed CoPt films, where long-range order is the highest. The structural study of these CoPt films grown on MgO(110) has pointed out that three variants of the L1{sub 0} phase coexist. The proportion of x and y variants, with the concentration modulation along a vector oriented at 45 degree sign with respect to the growth direction, is higher than the proportion of the z variant with the concentration modulation within the plane. The magnetic study shows an in-plane easy magnetization axis with a large magnetic anisotropy. This is interesting for the magnetic recording media with classical longitudinal writing and reading heads. The simulation of the magnetization loops confirms that the easy magnetization axis is within the plane and along the [110] direction, favored by the dominant x and ymore » variants.« less

Authors:
; ; ; ; ; ; ; ; ;  [1]
  1. IPCMS (UMR 7504 CNRS), ULP-ECPM-CNRS, BP 43, 23 rue du Loess, 67034 Strasbourg Cedex 2 (France)
Publication Date:
OSTI Identifier:
20982766
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 6; Other Information: DOI: 10.1063/1.2537515; (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; ANISOTROPY; ANNEALING; BINARY ALLOY SYSTEMS; COBALT ALLOYS; CRYSTAL GROWTH; DEPOSITION; FERROMAGNETIC MATERIALS; LAYERS; MAGNESIUM OXIDES; MAGNETIC PROPERTIES; MAGNETIZATION; MOLECULAR BEAM EPITAXY; PLATINUM ALLOYS; SIMULATION; SUBSTRATES; THIN FILMS

Citation Formats

Abes, M., Ersen, O., Meny, C., Schmerber, G., Acosta, M., Arabski, J., Ulhaq-Bouillet, C., Dinia, A., Panissod, P., and Pierron-Bohnes, V. High in-plane anisotropy of epitaxial CoPt(110) alloy films prepared by cosputtering or molecular beam epitaxy on MgO. United States: N. p., 2007. Web. doi:10.1063/1.2537515.
Abes, M., Ersen, O., Meny, C., Schmerber, G., Acosta, M., Arabski, J., Ulhaq-Bouillet, C., Dinia, A., Panissod, P., & Pierron-Bohnes, V. High in-plane anisotropy of epitaxial CoPt(110) alloy films prepared by cosputtering or molecular beam epitaxy on MgO. United States. doi:10.1063/1.2537515.
Abes, M., Ersen, O., Meny, C., Schmerber, G., Acosta, M., Arabski, J., Ulhaq-Bouillet, C., Dinia, A., Panissod, P., and Pierron-Bohnes, V. Thu . "High in-plane anisotropy of epitaxial CoPt(110) alloy films prepared by cosputtering or molecular beam epitaxy on MgO". United States. doi:10.1063/1.2537515.
@article{osti_20982766,
title = {High in-plane anisotropy of epitaxial CoPt(110) alloy films prepared by cosputtering or molecular beam epitaxy on MgO},
author = {Abes, M. and Ersen, O. and Meny, C. and Schmerber, G. and Acosta, M. and Arabski, J. and Ulhaq-Bouillet, C. and Dinia, A. and Panissod, P. and Pierron-Bohnes, V.},
abstractNote = {We present structural and magnetic properties of three sets of structures: as-deposited CoPt films cosputtered at 900 K on MgO(110) substrates with a Pt(110) buffer layer and CoPt films deposited by molecular beam epitaxy directly on MgO(110) substrates at 900 K, as prepared and annealed at 900 K. All layers have the L1{sub 0} tetragonal structure. The chemical long-range ordering for the as-deposited CoPt films is incomplete in contrast with the annealed CoPt films, where long-range order is the highest. The structural study of these CoPt films grown on MgO(110) has pointed out that three variants of the L1{sub 0} phase coexist. The proportion of x and y variants, with the concentration modulation along a vector oriented at 45 degree sign with respect to the growth direction, is higher than the proportion of the z variant with the concentration modulation within the plane. The magnetic study shows an in-plane easy magnetization axis with a large magnetic anisotropy. This is interesting for the magnetic recording media with classical longitudinal writing and reading heads. The simulation of the magnetization loops confirms that the easy magnetization axis is within the plane and along the [110] direction, favored by the dominant x and y variants.},
doi = {10.1063/1.2537515},
journal = {Journal of Applied Physics},
number = 6,
volume = 101,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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