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:
- University of Alabama, Tuscaloosa
- 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.
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.
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.
@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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