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Title: Magnetic Transitions in Lattice-matched, Ordered FePt 3 Based Antiferromagnetic/ferromagnetic Films

Abstract

Measurements of lattice-matched antiferromagnetic/ferromagnetic films which are ideal layered systems to study exchange bias are reported. Epitaxial films of FePt{sub 3} have two kinds of antiferromagnetic ordering. The spin ordering phase with wave vector Q{sub 1} = (1/2 1/2 0) has a Neel temperature T{sub N} = 160 K and that with wave vector Q{sub 2} = (1/2 0 0) has T{sub N} = 100 K. Neutron diffraction confirmed the presence of Q{sub 2} = (1/2 0 0) antiferromagnetic ordering in 200 nm Fe{sub 25}Pt{sub 75} grown on MgO(100). The loop shift and coercivity of a trilayer film of CoPt{sub 3}/FePt{sub 3}/CoPt{sub 3} decrease with increasing temperature, consistent with the observed Neel temperature of FePt{sub 3}. The x-ray diffraction rocking curve widths of films grown on MgO(100) and Al{sub 2}O{sub 3}(11{bar 2}0) are compared and related to the loop shifts that are observed in the films with lattice-matched antiferromagnetic/ferromagnetic interfaces.

Authors:
 [1];  [2];  [2];  [2];  [1]
+ Show Author Affiliations
  1. University of Alabama, Tuscaloosa
  2. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); High Flux Isotope Reactor
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1003572
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 99; Journal Issue: 8
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; NEEL TEMPERATURE; NEUTRON DIFFRACTION; SPIN; VECTORS; X-RAY DIFFRACTION

Citation Formats

Mani, P., Vemuru, Krishnamurthy V, Robertson, Lee, Klose, Frank Richard, and Mankey, G. J.. Magnetic Transitions in Lattice-matched, Ordered FePt3 Based Antiferromagnetic/ferromagnetic Films. United States: N. p., 2006. Web. doi:10.1063/1.2177347.
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Mani, P., Vemuru, Krishnamurthy V, Robertson, Lee, Klose, Frank Richard, & Mankey, G. J.. Magnetic Transitions in Lattice-matched, Ordered FePt3 Based Antiferromagnetic/ferromagnetic Films. United States. doi:10.1063/1.2177347.
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Mani, P., Vemuru, Krishnamurthy V, Robertson, Lee, Klose, Frank Richard, and Mankey, G. J.. Sun . "Magnetic Transitions in Lattice-matched, Ordered FePt3 Based Antiferromagnetic/ferromagnetic Films". United States. doi:10.1063/1.2177347.
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@article{osti_1003572,
title = {Magnetic Transitions in Lattice-matched, Ordered FePt3 Based Antiferromagnetic/ferromagnetic Films},
author = {Mani, P. and Vemuru, Krishnamurthy V and Robertson, Lee and Klose, Frank Richard and Mankey, G. J.},
abstractNote = {Measurements of lattice-matched antiferromagnetic/ferromagnetic films which are ideal layered systems to study exchange bias are reported. Epitaxial films of FePt{sub 3} have two kinds of antiferromagnetic ordering. The spin ordering phase with wave vector Q{sub 1} = (1/2 1/2 0) has a Neel temperature T{sub N} = 160 K and that with wave vector Q{sub 2} = (1/2 0 0) has T{sub N} = 100 K. Neutron diffraction confirmed the presence of Q{sub 2} = (1/2 0 0) antiferromagnetic ordering in 200 nm Fe{sub 25}Pt{sub 75} grown on MgO(100). The loop shift and coercivity of a trilayer film of CoPt{sub 3}/FePt{sub 3}/CoPt{sub 3} decrease with increasing temperature, consistent with the observed Neel temperature of FePt{sub 3}. The x-ray diffraction rocking curve widths of films grown on MgO(100) and Al{sub 2}O{sub 3}(11{bar 2}0) are compared and related to the loop shifts that are observed in the films with lattice-matched antiferromagnetic/ferromagnetic interfaces.},
doi = {10.1063/1.2177347},
journal = {Journal of Applied Physics},
number = 8,
volume = 99,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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Journal Article:
DOI:  10.1063/1.2177347
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