Magnetic structure determination for annealed Ni{sub 80}Fe{sub 20}/Ag multilayers using polarized-neutron reflectivity

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:225305

Borchers, J A; Gehring, P M; Majkrzak, C F ^[1]; Ankner, J F ^[2]; Hylton, T L; Coffey, K R; Parker, M A; Howard, J K ^[3]

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1. National Inst. of Standards and Technology, Gaithersburg, MD (United States). Reactor Radiation Div.
2. Univ. of Missouri, Columbia, MO (United States). Research Reactor Facility
3. IBM Storage Systems Div., San Jose, CA (United States)

Sputtered Ni{sub 80}Fe{sub 20}/Ag multilayers, annealed post-growth, show giant magnetoresistive (GMR) effects at unusually low magnetic fields ({approx} 5 Oe). Structural characterization by cross-sectional TEM and x-ray diffraction indicates that the Ag preferentially diffuses into the Ni{sub 80}Fe{sub 20} layers at the interfaces. Using polarized-neutron specular reflectivity, the authors have obtained magnetization depth profiles for a series of annealed [Ni{sub 80}Fe{sub 20}(20{angstrom})/Ag(40{angstrom})]{sub 4} multilayers. Though GMR in related materials is associated with coherent antiferromagnetic alignment of the ferromagnetic layers, specular neutron data for the Ni{sub 80}Fe{sub 20}/Ag multilayers show no trace of half-order spin-flip intensity characteristic of this simple structure. In small applied fields, transverse scans at the half-order position show a broad feature which disappears upon saturation. These data suggest that while the Ni{sub 80}Fe{sub 20} moments are antiferromagnetically correlated along the growth axis, the in-plane magnetic domains are only of micron-order size and are thus not apparent in a specular measurement.

• OSTI ID: 225305
• Report Number(s): CONF-941144--; ISBN 1-55899-278-2
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
66 PHYSICS
COMPOSITE MATERIALS
CRYSTAL STRUCTURE
DIAGNOSTIC TECHNIQUES
IRON ALLOYS
MAGNETIC PROPERTIES
MAGNETORESISTANCE
NEUTRONS
NICKEL BASE ALLOYS
REFLECTION
SILVER