Molecular beam epitaxy growth of exchange-biased PtMn/NiFe bilayers with a spontaneously ordered PtMn layer

Journal Article · Sat Apr 15 00:00:00 EDT 2006 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.2189935· OSTI ID:20788091

Choi, Y S; Petford-Long, A K; Ward, R C. C.; Fan, R; Goff, J P; Hase, T P. A. ^[1]

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1. Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom)

We report the direct epitaxial growth of equiatomic ordered antiferromagnetic PtMn layers by molecular beam epitaxy. Such layers are used in giant magnetoresistance spin valve sensors as the antiferromagnetic pinning layer. Structural characterization and phase identification confirmed the spontaneous formation of the chemically ordered face-centered-tetragonal (L1{sub 0}) phase of PtMn with about 87.4% ordering. Based on the antiferromagnetic PtMn layer, we prepared exchange-biased PtMn/NiFe bilayers with various PtMn thicknesses. The exchange anisotropy field of the bilayer with NiFe grown on PtMn stabilizes at about 50 Oe beyond a PtMn thickness of 15 nm. Although the exchange anisotropy field is small compared to that of the polycrystalline system, the antiferromagnetic domain structure is stable over repetitive external magnetic field cycling and no training effect is observed.

• OSTI ID: 20788091
• Journal Information: Journal of Applied Physics, Vol. 99, Issue 8; Other Information: DOI: 10.1063/1.2189935; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANISOTROPY
ANTIFERROMAGNETIC MATERIALS
ANTIFERROMAGNETISM
CRYSTAL GROWTH
DOMAIN STRUCTURE
EXCHANGE INTERACTIONS
FERROMAGNETIC MATERIALS
IRON ALLOYS
LAYERS
MAGNETIC FIELDS
MAGNETORESISTANCE
MANGANESE ALLOYS
MOLECULAR BEAM EPITAXY
NICKEL ALLOYS
PLATINUM ALLOYS
POLYCRYSTALS
SPIN